when you open the box of a rack effects processor all you get is the processor, the ac adapter, and the manual. maybe a midi cable.
when connecting a processor use the effects loop of your amp, do not connect the guitar to the effects to the amp. if you have a preamp then connect it between the preamp and the power amp. also to switch the programs in you processor you are going to need a midi pedal board, there are several that do a great job or you are stuck switching them by hand. as far as cables go you will need 2 regular 1/4 cables, input and output, per processor and a midi cable to switch the programs. if you are going to buy several processors i suggest you get a furman power supply to connect everything and also keep your rack organized and clean using the smallest size cables possible and using velcro to stick all the ac cords to inner wall of the rack. if not you'll see how quickly everything will bunch up. the processors sound great but you will need alot of patience and time to get the sounds that you like and with so many options it will drive you nuts a couple of times.