If you have a "BOOKMAN'S" store around your area, it's a FANTASTIC place to pick up old games really cheap. It's a used book/music/software chain.
In the past year-year and a half I decided to revisit many of the oldies I used to play and have found most of them there.
Ex. Wing Commander series, Strike commander, x-com 1-2, Lands of Lore, EOB 1-3, Full Throttle, Descent 1-2, TES 1-2, and many more
Most of them only cost $3-5 and the few I couldn't find there I got off of ebay. And if you don't have a Bookman's in your area, look at some used book stores. Sometimes they don't advertise that they resell software. $5 is a small price to pay for classics!
-Dj
"Mordrid"