I've only bought Janomes from a dealer, and they're really so easy to use I haven't really learned anything from the dealer classes. My dealer doesn't like to let you leave with your new machine until you can show that you at least know how to thread it (using their shop machines). When I was picking up my 6600 I sat down, grabbed the thread and had the machine perfectly threaded in about 3 seconds. It's pretty standard, and there are even arrows on the machine to help and a needle threader...how hard could it be? I still have something like 3-4 hours of free instruction time available on their books, but I'll never use it. The manual tells me pretty much everything I need to know.
If I had bought my embroidery machine from a dealer I might have learned something, but I bought mine on Amazon and have learned online and from the manual. Again...pretty basic as far as machine function goes. I still get mixed up on figuring out proper stabilizer for the fabric & design but some of that I think is just a learning curve that people have with these no matter what. There are general embroidery machine classes available locally that I could take for a nominal fee but I haven't bothered. I don't mind learning from experimenting - I remember things I've discovered myself better than I remember things I've been told anyway.