I think you really just have to go through as many names as possible, narrow them down, and try them out. In the beginning, I thought I should have a name close to my birth name, and I used Rafe for awhile, but it just didn't seem to fit. I had always intended Dean to be my middle name, and my wife one day told me, "I like the name Dean. I'm going to call you Dean." I realized I had really only picked the other name because I mistakenly thought I owed my parents something; however, my folks will always call me by my birth name. So I went back through all the old names and settled on Sebastien Dean... I think it sounds good together, and I just go by Dean or DeanO. It seems to work.
D