1          Magic Bullet
1          Probe
15        Firestorm
30        Icestorm
35        Firebolt
50        Lightning

Magic bullet and probe are learned in Guildhall.  Firestorm can be learned by doing the Mage guild quest in Stoneglow.  The rest are also learned in the same guild from different NPC inside.  Hope this helps. 

EDIT:  Oh and there's also now Icebolt, obtained from Captured Stronghold Ice king (or whatever his name is) , can't remember where the quest is from.