At work* this week I picked up a bag with 120 random AGOT cards. Best i can tell they are from the Core Set (50 cards, with T or B designation) and the rest (70 cards) are some sort of expansion (with an F designation)
Do these have any value? and by that I mean, would someone who plays the game have use for them (not "can I sell them and get rich" because: no).
Lots of Core Set cards are used by players. Many players have to pick up multiple Core Sets in order to get more copies of the Core cards, because Core Set is the the only LCG version that doesn't come with 3x of each card.
In addition, Core Set has a lot of basic staples that are used in many decks. So many players like to get multiples of these so they can have enough for making different decks without having to the same Core Set cards between each deck.
Depending on which cards you have, players could definitely have use for them.
Is there an easy way to figure out what set(s) they are from that doesn't involve looking up each card one at a time?
You can use either of these links:
Just sort the cards by their set symbols, look up one, and then you'll have the set identified for all the cards with that same symbol.