Hi. Congrats on the soon-to-be new gear! Looks like a nice set up.
To connect the receiver to the amp, and to connect the receiver to the subwoofer, you'll want some RCA cables. At Monoprice, I'd choose their "high quality" line like this example
here. I bought their lower line and, while they work just fine, had some trouble getting the connectors to stay on. My buddy bought their high quality cables and likes them.
You mentioned buying wall plates. Are you running a lot of cable through your walls? If so, be sure to get cable that is rated for inwall use like this
two-conductor wire or this
four-conductor wire. Just examples, of course - Monoprice has other lengths.