Probably very simple question. I am currently looking at getting a TV and a new iPhone. My current computersm a new iMac and an old G4 (plus my printers) are hooked up to each other via wired (Ethernet) network and router to ADSL. To go wireless with the TV and iPhone to search web and use iTunes can I just turn on WiFi on all three devices and set up a network, or do I need a SEPERATE wireless router/Air-base Extreme etc to set up a network? Thanks.