You can identify that it is an artifact (assuming it's small) by trying to pick it up with Mage Hand, failing (Mage Hand can't target magical items), then trying to Identify it (and failing - Identify doesn't work on Artifacts)
The Bardic Knoweledge class ability (and similar) can give hints.
The Cleric spell Commune can give yes/no responses about it.
The Sor/Wiz spell Contact Other Plane can give yes/no responses about it, too.
Wish and Miracle can do anything the DM says they can.
An appropriet (very, very difficult) Knoweledge check could give info.
Gather Information might bring up legends about it (good luck sorting fact from fiction, though).
Edit: But really, Artifacts break the rules. It's up to the DM to determine how they do so, and how you find out how they break the rules. Perhaps a Bardic Knoweledge check brings up that it was once studied by the great sages of Alexadria. The Communing Cleric can then find out that the book needed was checked out when the library burned. The Wizard might happen to know of a storehouse of lost knoweledge where such a book might be found. The Rogue will need to actually fetch it, however, as it's only accessable by a thin ledge in an Anti-magic field. The Fighter needs to keep his bow out, as those silly bats keep wanting to suck his blood while he does so.....