I need recommendations for microphones for MacBook (wireless microphone) or iPod (Wired or Wireless) to record Yoga sessions. I tried to record using Internal Microphone and Garage Band on MacBook, but the voice of the instructor got too weak when she walked around the studio and away from the MacBook). To make things worse, we have lots of loud fan heaters in the studio (It's Hot Yoga). I'm doing this recording for my personal use (My favorite instructor is moving next spring), so the budget is limited--maybe $150 at most. I appreciate recommendations for microphones and recording tips. Can anyone help me? Thank you in advance!