Springfield XD40
its compact, .40 cal, and looks nice. and can be had for less than $600. I have a Smith & Wesson Sigma SW9VE and I love it... but the trigger pull is very heavy... you may not like, plus its only a 9mm, which still would slow someone down. If you wanna go even bigger and have the money for it... get a Kimber Pro-Carry. Its .45 caliber and looks bad ass. I;ll post some pics in a min