[Al Skierkiewicz]

I know in a small home network you may not be concerned with speed but the suggestions thus far do affect connect speed and data loss.
A hub or router is the only way to reliably connect multiple lines. They are cheap and readily available through Best Buy, Fry's, etc. Even mailorder can get you one in a couple of days.
You can make your own cables but it is tricky to get them to pass 100Mbit data streams. If you can handle the lower data speed, a so-so made cable will pass 10 OK. Again, cables are cheap and easily available from the above sources.
If you are going to something, do it right and use the right tools.