Enough good things cannot be said about Dwarvenpaths! They made me a completely custom piece that I absolutely love, and they are very fair on pricing. If you need, or are thinking about, any leather at all, go to them!
As for other things, I got most of my garb from Medieval Collectibles.
Also, try a thrift shop in your area, you might find something you like there for dirt cheap!
OOG: Chris
IG: Benjamin Daimler
IG: Grobspit Snaggletooth G.D.S