Unless they are really rare, pitch the beat up ones, or try a garage sale. For the ones in good shape, the college kids are getting into vinyl, so they will go for the popular rock stuff in good condition (Beatles,Stones,Doors etc.) As a rule the albums that are really valuable are the oddball rarities in the rock/folk/blues field. I would go the Ebay route if you have any of these. You can get a feel for the values by checking the Ebay completed listings, but remember condition is everything. I have done quite well selling vinyl on Ebay.
Edit- I see you have a lot of 45's, if they have picture sleeves you can do well with many of those even if the records are not in the best of shape. Wish I was close enough to go through them. If you have any original Elvis/Beatles/Stones picture sleeves they should be worth something decent at worst.
post edited by flyseye - 2012/08/22 13:26:50