I was dis-satified with "off the rack" gun holster leather for a carry gun I had. One of the forums I belong to got a group together to learn how to make holsters at the Bloomington Tandy store. It really opened my eyes to the fact that I could make my own holsters and works well with my back ground in wood working, sculpture and engineering.
I put together some different holsters and posted them on our local forum and on defensivecarry.com. When I did, many "real" holster makers provided good feedback via posts and PMs (Nate from UBG and Bruce Gibson to name a few). From this, I slowly improved my holsters until people asked, "Can you make one for me?" Now I'm 9 months in and the quality is very good, good customer reviews and now looking to get a stitching machine because my punching and hand stitching can only produce so many holsters with my part time effort.
Now my self and another local forum member have been doing classes for forum members who want to give it a try! It is nice to pass on the knowledge.