Icom really is your best source. It's best to get the latest version of the software to prevent any issues and headaches. Programming cables are easily found. I discovered the cable for programming my old F420, F320 etc radios works fine with my Icom 2200 mobile. I've had mixed luck purchasing cables off of e-bay. Some work fine, others don't.
You can often find the software on the web, but you are sort of taking a chance on the unknown source. It could be good, it could be corrupt, or it may have viruses.