We Have Three Computers But Only One Connected To Internet. How Can A Second Internet Be Added?

[Lynd]

This assumes you have broadband internet(like that provided through DSL, Cable Modem, or Satellite):   Purchase a router(can be wired or wireless) from any larger electronics store or office supply place(Best Buy, Circuit City, Staples, Office Depot, etc.)  Most of the more popular routers will have the ability to support four or more wired ports in addition to the wireless feature, which really doesn?t add to the cost these days.  The more common brands of wired/wireless routers are LinkSys, DLink, Netgear, and Belkin.  There are certainly many others that work fine and almost all can be had for $30 to $50.   Once you have the router(which will have VERY easy setup instructions), you?ll simply place the router between your existing internet connection and your currently connected computer.  So your internet connection plugs into the router, then the router plugs into the network connection on your computer.  From there it?s only a matter of using the same type of network cables to connect from your other computers to the router.    If you go with the wireless option, you can eliminate the cable to each of the other computers and instead go with either their existing wireless network interface card(if so equipped) or purchase a wireless card or USB device, both of which can be found for about $25.   It really works almost that easily.  Hope that helps!