What is the most inexpensive way to add another cable line for a second computer?

Question

and how should I go about doing it?

Answer 1

You would probably be better off getting cheap switch or hub, and running a separate ethernet cable to the second computer - total cost less than $50.  If you get a second installation of cable the cost will surely be more than that.

Answer 2

If you have a cable modem - with a cable going from the modem to your computer - you need a switch and 2 more cables

Connect the cable modem to the port on the switch midi or uplink port.  Connect cable from each computer to RJ45 ports - thats it

Zonet 5 Ports 10/100Mbps Ethernet Switch: ZFS3005P (Retail)   NTSWZNZFS3005P  $21.99

Category 5e RJ45 Network Patch Cable - 10 Foot: $4.99

Answer 3

A new outlet would cost around $10 dollars probably, and you would have to rent another modem. You are better off buying a router and running the second computer either wireless the router, or running a new ethernet cable from the router to the other computer.

Answer 4

Get a router.

Just add another cable modem,