How can I find out how much my ooooold Pokemon cards are worth?

Question

I have two different Pikachus, a holographic Nine Tails, Vulpix, Eevee, Jigglypuff, Sandshrew, Koffing, oddish, Cubone, Dratini, Weedle, Lickitung, Marowak, Rattata, Rapidash, Charmeleon, Bellsprout, Charmander, Paras, Bulbasaur, Psyduck, Poliwag, and Geodude

any help will be greatly appreciated!

Answer 1

Check them on eBay. Just key in the card in the eBay search bar, and they will show you a lot of listing for the cards.

Answer 2

Yes, eBay is a good place to check.