Are you looking for a list for valuation purposes to see what discs are worth the most or simply an idea of what discs are important from a historical perspective that are no longer available?
One thing a person can do to see what collectible discs are currently in high demand is to go to Ebay and sort all golf discs for sale by price with highest first. Here is a USDGC Roc that is going for well over $100 right now
http://cgi.ebay.com/Disc-Golf-Frisbee-179g-2002-USDGC-Roc_W0QQitemZ320313514880QQcmdZViewItem?hash=item320313514880&_trkparms=39%3A1|66%3A2|65%3A3|240%3A1318&_trksid=p3286.c0.m14.
This doesn't always mean the discs are worth as much as the beginning bid or buy-it-now price you see though. Only discs that are being bid on can be assumed to be in demand. Just like anything else, they are only worth what someone is willing to pay no matter what any sort of collectors list says.
There are several of my favorite discs I know of that consistently sell for $30 or more.
Innova - Griffin (discontinued in 1996)
Discraft - First Run Z Buzzz
Innova - 10x Cheetahs and most other 10x discs due to the fact they were the first to be made with what was to become CE plastic.
Innova - Special Edition Valkyries, Tee Birds and others. (SE Valk)
Innova - CFR (champion fund raiser) discs that are produced in limited quantity in a higher quality plastic like the 2002 CE Gazelle and the CFR Classic Roc (I forget what year that was but Jack is a collector of these).
Lightning - Any of the original issue "airplane" stamp discs such as the Spitfire and others. (reissues do exist and are marked as such)
Innova has a lot of early (80s) golf discs that you don't see up for sale much but can be considered collectible. Discs such as the Coupe and original Eagle fall in to that category.
Rare stamps can be collectible for their aesthetic value but don't necessarily hold much monetary value unless the disc itself is in demand. Tourney stamps from defunct tournaments and things of that nature can be cool to own as works of art or whatever but there's thousands of them floating around.
If you are talking strictly about golf discs there's a lot to consider as to whether something is collectible in my opinion.
