Multimeter

Damn that fluke ****. I got this one from Harbor Freight and it works GOOD. Waste your money if you want to, but for what you're probably gonna do, this one will more than likely do the trick. If you don't like it, you can always take it back.

http://www.harborfreight.com/5-in-1-digital-multimeter-98674.html

thats a significantly higher quality HF mulitmeter than what ive had the pleasure of using

My experience has been these that would go onsale for $6.99 or so. Damn $3 on sale now which makes it only $2.99 over priced ;-)
http://www.harborfreight.com/7-function-multimeter-98025.html