Hello,
The easiest way to do this is with a router. You can pick up a simple router for under $50 in any store that sells computer equipment (Best Buy, Walmart, etc.). If you want the ability to connect wirelessly, it may cost $70 or $75.
Your DSL modem connects to the outside connection on the router. Your other computers can connect to one of the internal ports on the router. In most cases, your router is set up to work right out of the box. No additional programming or settings changes are needed.
Personally, I use a Linksys router for my home network. I think Linksys is the most popular but there are many good and inexpensive brands out there.
I hope this helps!
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