I with tiscali and find there service very good, well priced and its unlimited. The only ISP that I know of that doesn't have a 12month contract is virgin but having seen the problems a friend is having with them and reading some stuff on the web I wouldn't recommend them. Plus they still charge you a 50 quid leaving fee if you cancel before 12months.
As far as webspace goes you can get free webspace from bravenet or do you need something for business purposes.
Connecting the two PC's together, I would say getting a wireless router and wireless card for one pc. The other one would connect to the router using a network cable.