As a long time C64 owner and a guy who still has a real Commie hooked up in his computer room, I have to admit that I do most of my C64 game playing via emulation. I'm not saying it's as authentic but it sure is a lot more convenient.

Track down one of the GameBase releases. They are up to version 6.0 now but for most people, the changes between even something like version 3 and version 6 are relatively minute (what's a hundred games in a collection of 20,000?). As far as I know they all (or at least the vast majority) work in WinVice. I second Mayhem's recommendation of putting WinVice in true 1541 emulation mode and then hitting alt-w to warp past the load times ... the true emulation mode loads a lot more "non-cracked" titles.

Two collections I recommend are the Blast Collection and the Arcade Collection. I don't remember when or where I found them, but each one contains over a thousand games and both weed out a lot of the crappy BASIC games that you end up getting. Just like iTunes, with such a large library, there's a lot of low quality crap out there and some of the collections like Blast have weeded a lot of it out for you.