It's pretty simple really, if anyone has instructions on how to do this, I would appreciate it. My router is on the way, but I don't want to wait, I have a switch, a cable modem and 2 macs with mac os x, can I configure one of the macs as wired and wireless router?
Yes you can, plug one of the Mac's in directly to the cable modem (make sure the firewall in enabled first!) and setup Internet Sharing in Network Preferences to allow the other Mac to connect wirelessly. See these instructions from life hacker.