Here's a few suggestions. I don't know exactly what you need or what your budget is, but I would start with Hemmings Motor News. This publication is the bible of collector car hobby and prople are always selling parts, and there are places parting out cars out west. They can be found at:
http://www.hemmings.com/
Here are a few more places to try;
http://www.ecklers.com/?cm_mmc=Googl...00000000019728
http://www.madvet.com/shop?referrer=...FSE7GgodEgWBCQ
Also another thing to consider is some of what you might need might still be available from GM. Ya just have to find someone with a GM catalog to get part numbers, then you take the part numbers to a GM dealer and have them check the history and availability to see if you still can get them from GM. More than likely interior trim will all be discontinued, but mechanical parts such as brackets etc. might still be available. I have a catalog, as long as you don't need a million parts looked up I might be able to supply you with the original numbers. I would suggest subscribing to Hemmings, as it is the bible for old cars and parts, plus it's a great monthly read.
Jeff
http://www.corvetteamerica.com/
http://www.zip-products.com/Zip/asse..._corvetteparts
http://www.corvettecentral.com/
http://www.corvettesalvage.com/
here is a whole list for you to go thru
http://web.info.com/infocom.us2/sear...=3044&tpxnws=1