I was VERY fortunate to build my collection of these fine CDs by haunting used CD stores. It took me awhile, but I've got most of them now. Don't cry but, I was able to pick mine up for about $5.99 a piece at different Disc Replay stores !
Toward the end of the series of the Classic Rock collection, there are a few CDs that are kinda hard to come by on Ebay, BUT, those couple CDs have REAL obscure tunes that I probably wouldn't use for events anyway, so I really don't persue those. However, even those CDs are nice to have if you're a real purist for classic rock and off the wall tunes.
Another good set is "Malt Shop Memories". I think these are also Time Life discs, and I think there's 12 or 15 in the set. I also have a 4 CD set put out by Readers Digest ( believe it or not ! ) called "The Heart And Soul Of Rock n Roll".
Whatever you do.... MAKE SURE you get ORIGINAL RECORDINGS by the ORIGINAL ARTISTS !!! There's alot of rip off oldie sets out there.
I still see these Time Life CDs at used CD stores, so my best advice would be go to as many of them as possible and build up your set that way.
Nice chattin with ya. Good luck.