The Magicka Complete Pack is on sale at GamersGate for only $7.99.
It comes with Magicka, Magicka: Vietnam the expansion DLC, and the Wizard’s Survival Kit DLC. Offer expires tomorrow (about 15 hours left).
Or if you just want to pick up the base Magicka game it’s on sale at Amazon for only $4.99.
No matter where you buy the game it will activate on Steam because it uses Steamworks.