There are 2 places you could get a good price range. I would look in your local phone book and see if any local sports/memorabilia card shops could give you any information. They may ask you to bring them in or they might know someone in your area who might be able to give you their value.

I wouldn't sell them to a card dealer who will just resell them since you will be less than they are worth..they have to make a profit too ;)

The other option is to gauge the price of comparable items on Ebay. Or, once you have the price from you local source, you can sell them on Ebay at that price (or better)

Good Luck!