I started the game not really knowing what type of character I wanted to make, I put all my point into destruction / restoration but used a one handed sword and light / heavy armour. A very random class I made...

I also put a perk in something I didn't want, is there anyway to undo perks? Also, where is the mages style guild in Skyrim? I'm level 7 and I've only met the companions as Nord so far.

Play a bit more, you'll get sent to near the "mages guild" eventually. They are under a new name which i can't remember at the moment but its some magic college