There's a post above I started a while back seeing how other big guys managed to conceal their weapons. I kind of rigged my own belly band with a cheap nylon gun belt/IWB hoster combo that I either carry above or below my beltline with the weapon at anywhere from 9:00 to 3:00 (depending on which gun I carry and what I'm wearing).
The bellyband looks a little uncomfortable (girdle) and the "SmartCarry" holster shown in that thread scares the hell out of me to be honest.
A lot of bigger guys chose to get pocket guns and pocket holsters or go with a small frame semi/revolver IWB from what I have read.
