Hi William. You also might want to check in on the Team Camaro site. There's tons of people on there all the time for your more basic questions, such as the one you posed (not that you can't ask here as well). CRG is invaluable for technical details. While my post numbers are low here, I'm often on this site doing research or, as you stated, looking at old posts for details already provided.
Prior to starting my restoration, what I did was, contact all the major Camaro parts houses, ordered a catalog, and then did a price comparison of each for the parts I was going to need. If you are doing a large order all at once, some places give you a bulk discount. Others often have specials or big 20% off sales during certain times of the year. I think you'll find that you'll end up using quite a few different parts places over the course of your resto. For some reason or another one part might be $50 less at one place than another, and then another part it might be vise-versa. It's very odd.
In any event, some of the major parts houses for Camaro's are the following:
Classic Industries (probably has the largest selection of parts and are the "maker" of most OER (original reproductions))
Ground Up (there's a membership discount if you join Team Camaro)
Ricks First Generation/Ecklers (believed both are owned by Ecklers)
NPD
Bellair Bob's (good for sheetmetal)
Legendary Auto Interior (just started making seatcovers for '69 Camaros. they are nice--just got a deluxe set in green)
Heartbeat City
Classic Industries probably has the best catalog out of the bunch--very detailed photos and descriptions, so it's definitely worth getting that.
There's a few more that I'm probably getting, but this is the step I'd take if I were you.
Hope that helps some.