Basically, the "specs" for a microphone for a sound card are as follows:

High impediance, cardioid (unidirectional), dynamic microphone with a mini-phone plug connector.

Anything that fits those specs should work quite well. If you are planning to input music, though, don't do it through a mic. Use the card's "line input." For this, you need a player (CD, tape, etc.) that has a Line output as well.

Most high impedance mics are pretty cheap. Don't bother getting an expensive low-impedance mic for this application because the mic's output level won't match the card's designed input level and you will get an "impedance mismatch." Some "AGC" (Automatic Gain Control) circuits can handle either type of mic, but I wouldn't suspect that sound cards are designed that way. I haven't tried it, so that's just my suspicion.

Hope this helps. Good luck!

Dale Jay Dennis Sr. Television Technician