homeboyJim:
You will need something to record your creations with. The simplist solution is to connect a cassette deck to the line out of the RS7000. A better solution is to use your PC to record your stuff.
You can get Cool Edit 2000 freeware from
www.tucows.com. This software will let you record WAV files on you PC. This assumes you have a PC with a soundcard with a line in.
As for other stuff, I am assuming that you have an amplifier (can be receiver) and speakers so you can hear what you are doing. However, you can get by with a pair of headphones.