While ghosts have been dealt with many times, and Elementals are covered as well I believe, I was wondering how people deal with the issue of other Spirits of various realms in the game. Is there much information on where one can find say an Ignem spirit? Does every fire have one? (I'd be tempted to believe that any fire in an aura might, but most ordinary fires do not? The setting is NOT animist after all?) And what does a corpus spirit look like? Any ideas???
cj x
Something like an anorexic supermodel perhaps? 
Seriously though, on page 66 (top right column) of TMRE it seems to be suggested that a Corpus spirit would in fact be a ghost (as that is the spirit of mundane beings or otherwise deceased corporeal non-animal beings (humans pretty much). Under the heading "Finding a Suitable Spirit (for Spirit Familiars) the "where you might find such" question is ever so briefly touched upon.
I would suppose that Elemental spirits would be found in particularly strong arcane untamed locations (away from human settlement) such as a volcano of legend (Vesuvius, Etna, etc.) where people might have worshiped in pagan epochs (Fire Elementals), Other non-volcanic mountains/plains of ancient battles/etc (Earth Spirits), Mystical Lakes, streams, rivers, etc. (Water Spirits)..et al.
Without going on at length I would think the matter to be more an intuitive one as to where one might find the particular sort of spirit he/she was seeking.
In addition to the information in TMRE in the section on spell binding and hermetic empowerment, there is a bit in HoH:S on the Titanoi (in the Tytalus chapter), and IIRC another bit in the section on Sahirs (in the Ex Misc chapter).
For myself, I have collected my thoughts on the subject here, which I shall now post:
On Spirits
Mythic Europe is awash with spirits. Every inanimate thing has a spirit, and magic can be used to communicate with it or even infuse it with power and volition. Such spirits typically have a broadly human like perception (they can hear, see, and so on) but an alien perspective that shapes their interests, awareness, and memories. A spirit of fire, if asked about a conversation, might only perceive those speakers that its light glanced on, and describe things in terms of passions, tones, and action – it won't speak of the content, just like a person won't usually notice the speaker's scarf color or remember how he held his fork. An object's personality varies, but is generally related to its construction and nature (jewelry tends to be aloof and haughty, stones dour, and so on). Inanimate spirits are creatures of no name and low cunning; they can talk, given magic, but they do not posses true Intelligence. They have no names, like wild animals. Such spirits are commanded or controlled by the appropriate Form (so a spirit of fire would be affected by Ignem), and addressed by Intellego. Animals are simply “inanimate†objects with volition, and plants have lesser volition.
Inanimate spirits which are exceptionally true to their essential nature are beings of Magic. An object might posses raw vis, a creature might posses Magic Might (and often magical powers), even a place might be endowed with a magical spirit, a genius locus. Again, such spirits typically are merely Cunning, possessing no true Intelligence, and do not naturally speak nor have a name. Some, however, do have a name and/or intelligence. Magical spirits, whether creatures or places, are fairly rare except in high magical auras. Even in low magical auras most things have merely a lowly inanimate spirit of no Might.
There are also similar spirits of immaterial things. There is a spirit of love, which is present when lovers meet just as the spirit of fire is present in the bonefire. These spirits may be of any Realm, although they are most often beings of faerie. Spirits of evil things, such as lust, are often Infernal. Only a rare few are truly Divine, like the spirit of true love. Unlike inanimate spirits, such abstract spirits often have a very fleeting existence and are very weak and confused. Each is, however, a part of a greater spirit of the concept in a sense, and theurgists can sometimes channel aspects of these greater spirits. These are true beings of Might, possessed of Intelligence and having their own True Name. They are known as daimons. Unfortunately, most of the Magical daimons known to Hermetic theurgists are of somewhat unpleasant concepts such as war or intrigue; perhaps this is due to their usefulness.
People have a corporeal body that is subject to the art of Corpus and has an inanimate spirit of itself, separate from the active spirit of the person. Like other lowly inanimate spirits, it can be communicated with. It is a thing of low cunning and bodily desires, and often of a personality unlike that of the person, lacking in restraint and thought and prone to emphasize sloth, hunger, and bodily aches. It remembers the person's life, but largely in these terms, although the memory of a body's death is usually well seared into its psyche.
But people also have an animating spirit, unlike most other beings in Mythic Europe. It is a creature of Mentem, possessing Intelligence and a True Name, and has mastery over one's body except in sleep. It is the animate spirit that maintains man's memory and intellect, his thoughts and emotions, his perception and awareness. Body and mind are nearly inviolate and as long as a person is alive Hermetic magic finds it difficult to separate the animate spirit from the corporeal body, create a new one to usurp it, or so on. In death, however, the corporeal spirit is separated from the animate one on a mystical level. The spirit at this point acquires, for reasons unknown, a Might score, affiliated usually (but not always) with the Magic Realm. It usually drifts into the appropriate Realm in time. A few restless spirits haunt the living. Even fewer – of Divine Might – ascend directly to heaven.
The spirits of the dead, ghosts, can be affected as normal by Hermetic magic (although a magus cannot actually touch the incorporeal ghost's apparition). Their bodily remains and the place of their death serve as arcane connections to them. Certain magi, most notably leadworkers and certain theurgists, can also use a ghost's name as an arcane connection to it. Certain rites, such as Christian burial, may also prevent magi from affecting the spirit, and Hermetic magic cannot affect spirits that ascended to Heaven.
It is unclear how this relates to the matter of the soul. If there is such a thing, Hermetic magic seems unable to relate to it. Some speculate souls fall under the art of Vim, as it is this Form that affects angels and demons, who are thought to be made of soulstuff. Although the Order has been able to create a human spirit using Creo Mentem rituals, these spirits are found to be lacking in some ephemeral quality that prevents them from learning and they tend to be especially susceptible to the Infernal and lacking in moral fiber. Many magi speculate that the missing component is the soul, which lies beyond the reach of Hermetic magic.
Excellent thoughts YR7, i agree entirely. Never really thought about ghosts as spirits of the flesh, but its a nice way to look at them that fits into a coherent world view.
This also makes the world "almost" animist. The main difference being that most spirits are invisible and inert until magic grants them function. I don't like the idea of an animist world for Ars but this seems ok.
This is a large chapter in RoP: Magic, which I've now turned over to Atlas. Thus, it really should be the release after Art & Academe.
Yes!!!! 
This book was a distant something I longed for, and to suddenly have it become more real is a pleasure
Good news. 
8)
Hmm.... interesting.
Never thought of spirits being that common in ME. It looks too animist to me, and I am not sure I really like it.... However, I really liked YR7's overview, so I have mixed feelings about this. 
I prefer more christian/monotheistic approaches to this.
I tthink that magic can affect stuff becuase God wants magi to be able to affect it, not because you can manipulate a spirit here and there. For example, I would not say that a fire has a spirit: what it would have is stored information and the magi can extract it using their Ars Magica. The fact that magi perceive that they are talking to the fire is pure cosmetics: there is nothing to talk to in the fire. The fire siimply has stored information and the magi can extract it with more or less difficulty.
Now, there are spirits around. Powerful stuff (castles, cities, primal forests...) can have protector or/and resident spirits. A castle would have a spirit, for example, but not a crenellation. You can affect the crenellation, but that is not you affecting the spirit; there is none to be affected. The genius loci of the castle might get upset if you start doing weird stuff to his house, though.
Will try to expansd on this later. I ahve to updater Barcelon'as airport route map before that.
Cheers,
Xavi
(double post, ignore)
Without magic, only the Divine (ie Priests) interacted with these, and that mainly with Ghosts, rather than spirits. (Priests rarely caring about the spirit of a great oak tree in the middle of the forest, or even wandering near one, much less becoming aware of it.)
There is some debate as to whether Pagans prayed to Spirits, or Demons, or a combination of both, depending. (In ME, that is, natch.)
For spirits Mysteries Revised also mentions that the appropriate element serves as an AC to an spirits in the area. The example given is a fire for ignem spirits. Take a look at both spell binding (pg 27 MR) and hermetic spirit magic (pg 64)
Yeah I wrote that. I would usually restrict it to fires in auras though - but I can see the covenant hearth having a fairly strong spirit. The gargoyles in the cathedral may have Divine Terram spirits - the pool in a faerie glade a faerie Aquam Spirit, and so forth.
I quite like Yair's idea of everything having a spirit which is interrogated by Intellego spells, but most will be of no might at all I suspect - might - bah phone...
cj x