I usually do as much as I can myself, then get my son to look at it before taking my machine anywhere. There's not anyone close by (less than an hour drive) and I don't really know anyone to ask about who to go to. Seems like the going rate for service is pretty expensive so I try to just head problems off ahead of time.
Used to be able to find someone fairly easily, but many of these fellows have retired or passed on. The last guy I took mine to was in his 80s.