jagshouse.com
he's got everything for old Macs! Run System 6 on that puppy, not system 7 or 7.1. 6 might not be as "new feeling" as System 7, but it'll sure be "quicker feeling"! lol
the Mac Plus is great, but there's some things to remember...
1) Don't EVER block the ventilation slots on the side or top. If you do, it can cause irrepairable damage to your Mac.
2) Don't format high density disks as low density and expect them to survive for a long time.
3) Don't open it up. That's a CRT and it CAN KILL YOU. Stay away from it unless you know what the Hell you're doing!
4) Start regularly reading sites like lowendmac.com.
5) Love your little Mac like it's a member of your family and it'll be with you for years to come