http://www.gunbroker.com
http://www.gunsamerica.com
http://www.ebay.com
&
Check the gun shows. Word of warning though. I wouldn't buy a used one over the net and would look one over very carefully if buying one in person. The hi-cap magazines were not that tough and rough and tended to seperate/split/break at the plastic seams. I have been seeing some new ones on the above gun auction sights lately, though their going to run ya'.
Tick a Liberal Off, Buy a Hand Gun!
http://tscott.fws1.com
ONE NATION UNDER GOD!