If you do not know how to use a sewing machine, it would be extremely helpful to buy from a dealer who offers free lessons. I agree with buying a used machine if the dealer will offer lessons with it. Your Quilting 101 class will expect you to know how to use the machine, including how to thread it, how to wind a bobbin, how to insert and remove a bobbin, etc.
An alternative to dealer lessons is if your have a friend or relative who could spend an hour or two with you, teaching you how to use a machine. After that you will need to spend some time practicing to make sure you can do everything on your own before starting the quilting class.
If you can get free lessons only by purchasing a new machine, I would stick to a lower-end machine. Babylock, Brother, Janome and Sears Kenmore all have reasonable quality lower-end machines. Just be sure you are able to adjust the stitch length and stitch width individually. (The lowest-end machines often have a set number of "preset" stitches which do not allow you to make adjustments.)
This low-end machine can become your backup machine and take-to-class machine for later on, when you buy your all-bells-and-whistles more expensive machine.
Don't spend a lot of money on a machine now, before you really understand sewing machines and what you like/don't like. You could regret the purchase later, when you realize that this first machine doesn't have everything that has become really important to you. Give yourself some time.