I use that site, as well, but I really liked the number of filters you could set on PriceGuide.cards. I'm just not sure what happened to it. You can still see the filter categories, but you can't see any of the options. I think it must have something to do with the way the site is being rendered or something, and the owner just hasn't kept it current.
All New York Yankees cards are welcome to join my collection.
I'm also interested in recreating my main childhood collection, which consisted of mostly 1974 and 1978-1982.