Well, I have some money to spend and I have decided to spend it on a mixer and a few mics. I record mostly choral and theater performances and I have decided that the way to go is to buy a few mics (3 or so) and place them surrounding the stage area. Then I will run the mics into my mixer, and feed the mixer to my camera. I already own a Sennheiser K6 with ME66 and ME64 capsules. Does anyone know of some cheap mics that perform well for their price range? Cheap means under $100 a piece. Thanks!

The Sony ECM-MS907 Stereo is pretty good. You may also consider the Crown Sound Grabber II Boundary Mic.

If you really must stay at that price level, then the AKG D880 is currently being sold for 2 for $100. This is way below normal and many times less what the mic is actually worth.
If you could go a little higher, like $170 each, the Audio Technica AT3031 is an awesome mic for the money. Very low noise, high sensitivity and high max spl with a wide frequency response.
If you stick with a less expensive mixer like a Behringer, then you might could spend more on the mics.