be careful with the portal spell. they are available as a Level 5 Air spell pick, and you CAN find books for them. its hard to find BOTH books, and you DO need both books for the spell to work. often you will find many Set Portals while never finding a Return Portal.
there are also physical teleporters in the game.
when you meet other races and ally with them, thru doing little tasks for them, you will find they have teleport machines that take you to certain places that you have already encountered.
in fact, you have prolly seen 2 locked buildings in the countryside, maybe even used them to hide from local beasties. those are the tp target locations for each races' machines.
so get going!
you gotta lotta work to do.
V***V