On eBay I found a great mic: Shure sm57. $60.00 and below is a great price. I really like this mic, since it can be used for both instruments (mic guitar amps for recording) and vocals. That's all SoundGarden uses - so good enough for me. I am without PA (not presently in a band), but have the mic go into a desktop mixer and some basic rack effects (compression, EQ) and mixer output goes to a home stereo.
Admittedly, this is decent for recording, but inadequate for live performance. Happy jams.