Bestbuy offers Insignia - USB Microphone for $22.99 (orig. $39.99) with free shipping.

Product Description:
Get great vocal audio for streams and recordings with this Insignia USB microphone. Minimize background noise with a powerful cardioid recording pattern and monitor status via an integrated LED indicator. This Insignia USB microphone is adjustable for perfectly angled recording, while an included desk stand and mounting hole grant varied positioning options.

• Compatible with Mac and Windows
  For use with your existing device.
• Cardioid pattern
  Picks up your voice and insulates it from other signals.
• Desk base stand
  For optimal positioning.