Help! setting up a network!

[Runningkid]

i have jsut built a new system, but now i want my old PC as well as this one to have internet access

i have a USB modem.

What else do i need to set up this network. I ahve got a mate and he shares his internet but one of his PC ahs to be on all the time, i dont want this please help me. Also he sed something about crossover cables from RJ45 to USB or something, please explain

thanks

 

[Runningkid]

i m on ADSL atm, so if i have a router is taht all i need? my USB modem atm can go in the bin?

 

[Runningkid]

ok thanks