Most USB printers these days are Mac compatible. Scanners too. Try macmall.com, macwarehouse.com, etc.
One nice thing about Apple's OS is that most networking software is built in. I have a laptop and a desktop computer in my house. They are both tied to my cable modem via a router. I have only one printer, but I can print from either computer. The OS lets me use the desktop computer as a print server and share the printer from the desptop computer to the laptop (wirelessly, of course). And the best part was that there was literally NO setup required. The OS recognizes when a new piece of hardware is connected to the system and has built in drivers for most models.