Skate or die and Airborne Ranger were two of my favorites when I was growing up, I found them at the CCAG show and got them for $3 each. I almost got maniac mansion too but he was testing the disks before he sold them and it wouldn't load.
I was so excited to see some c64 stuff, I haven't seen any at yard sales or thrift stores in years. It seems strange since Ohio is right next to PA where commodore headquarters was, you'd think there would still be a decent remnant of stuff around.
I've been playing the NES version of skate or die and I've got to say a much prefer the C64 version, the graphics and animations seem more refined and you get to pick your board color and it saves your high scores. Strange enough I miss having music in the skate shop, I thought it was in the c64 version but it isn't (and of course the c64 music that is in the game is much better than the NES music) Another weird thing is that the NES version of maniac mansion has music but for the most part the PC version does not.