Most likely you'll want a large directional condenser, AKA a "shotgun" mic, which is what is normally used on film sets as a boom mic. You can get an Audio Technica ATR-55 Condenser shotgun mic on Amazon for $53.00. It should serve your purposes quite well.
Here is a link:
Amazon.com: Audio Technica ATR-55 Condenser Shotgun Microphone: Musical Instruments