Most larger cities and matropolitan areas have several places from which you can rent anything from microphones to PA systems to digital betacams to mixing consoles.
Rental for microphones is a great idea for those of us who can't afford the big Neumanns and Royers and such, but who could really use them for a key recording gig.
Some retailers will do it and some won't, you'd have to call the ones in your area to find out. If they don't do it, they should be able to tell you who will.
Often the best place to go for such stuff would be a place that rents equipment for theatrical, stage and movie production.
Probably the easiest way to find them in your area is to look in the local Yellow Pages unter "theater", "rental", "audio/video rental", "stage equipment", etc. Between that and a few questions to local retailers, you should be able to find a source pretty easily.
HTH,
G.
