What position pillows/wedges are best for beginners?

I have this inflatable one, and it's great, and inexpensive. You can fit a pillowcase over it, which means you can just toss it on the bed with the rest of the pillows without anyone paying attention to it. Inflatable cushions are also more customizable - you can deflate them a bit to adjust the size and pressure.

If you do get it, you'll want a foot pump or compressor or something. It'd be a monster to try and blow up manually.

maybe the Jazz. it is pretty small and not too expensive.