I have found ebay is the best place to find accessories.  I have noticed local tack stores beginning to stock things like drawer pulls and such.  I asked this same question a long time ago and people referred me to Jazz Sales.  They have a wonderful website and lots of stuff, but you need to be a dealer to buy from them, I am not.  So I got most of my stuff off of ebay or catalogs like Rods and stuff, they sell wall sconces.  If you want the western look, these are probably your best bets.

Good luck!!