As for salvage yards, haven't had much luck finding jeeps there. There is a 4x4 salvage yard in pasadena that deals specifically with Jeeps. Not the easest to deal with some times. Pasadena 4x4 Salvage, on beverly rd.
Depends on what you're trying to do imo. If you're going for a refurb, then you may want to start with a place like Morris 4 x 4 Center (online). Just patching it so that it gets you from point A to B = Craig's List or local forums. Good luck