My dryer stopped turning but still shakes when on and I think gives out heat
Yes, it could be a snapped belt. It could also be a seized motor or a broken pulley.

The first thing I would do is look for disassembly instructions for your dryer. Some owners manuals include this, but for most you need to find the service manual. Come careful Googling with your model number may yield a PDF of the service manual.

Once you open the dryer, it will probably be obvious what the problem is.

From there you can order the part through the manufacturer or from someone else like http://www.repairclinic.com/. I've used them quite a few times.