I have an IWB rig from AKJ Concealco for my Smith Shorty-Forty. The belt loop is actually placed behind the trigger gaurd, which helps minimize the holster's bulk. Although it took about six weeks to get the holster, I am extremely pleased with it.
I also have a ARG from Mitch Rosen for my Smith 4586. Expensive! Not particularly comfortable either. It shifts around too much. Stay away from 999 Holsters and Gear. I ordered a Kydex IWB for my G23 and a paddle for my G21, after being suckered in by the low price...The paddle conceals about as well as a cement block and the IWB makes my G23 look like a 6" long hunk of 4X4 post. They're not particularly secure either.
Other good bets: I have a Tauris IWB (with rough-side out)for my Sig P229 and a Galco Royal Guard for my P220.
For the money and the craftsmanship, I'd have to say the AKJ and the Tauris are my favorites.