Machete Mfg has several shirts as low as $3.00 in their clearance section from bands such as The Exploited, F-Minus, Lars Frederiksen and the Bastards, Rancid, Throwdown, and The Virus
http://www.machetemfg.com/index.asp?PageAction=VIEWCATS&Category=371
Shipping can be kind of high ($11.37...