You have to have teleporter scrolls in your inventory to use teleporter stones. The teleporter activation scrolls are the red ones and the map is green one in your inventory. You should have the related race's activation scroll to use a teleporter. Open the map and look if you activated the teleporters. You can only use the activated teleporters.
I have found that if I activate the Teleport Stone first and then decide to leave the scroll at home in my chest that the Teleport stone still works even if I don't carry the scroll with me all the time. <img src="/ubbthreads/images/graemlins/smile.gif" alt="" /> So....you can activate the stone and than leave the scroll at home in a safe place. <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />