I too load for .38 and .357. The .38's are primarily for practice/plinking, so I don't worry too much about group size or velocity. My load of choice is 3.0 gr of Bullseye underneath a 158 gr cast RNFP.
For the .357 I use 13.5 gr AA#9 with the same bullet. I've tried this powder with charges between 11.5 & 15 gr with no noticable changes in accuracy, but then again, I was shooting off-hand so small differences wouldn't have been noticable. 13.5 gr gets me about 1600 FPS out of my 1894c, which is about the same as a factory load. It also allows me to get 500 rounds out of a pound of powder, which I find real convenient. Most importantly it shoots well.
For me long range accuracy isn't an issue since all of my shooting is at 50 yards or less, you're situation might be different. Other than that, the process of working up a load is the same as a rifle, the only difference is the size of the powder charge.
Lotsa folks like 2400, 110/296, and 'Lil Gun for the .357. I use #9 because it allows me to use a standard primer as opposed to a magnum primer. For the .38 it's tough to beat Bullseye.
Good luck with your reloading, be sure to post your results.
GH1