So you're building a wireless rover...
Heres two options I would personally look into
1. This is rather difficult but cheaper
Use a Wifi Cam a.k.a IP camera aka Network Camera
Also use this : http://curiousinventor.com/kits/spk_wrt
to control the motors and stuff from the internet
2. Easy but more expensive - probably cost you around $500 to $600 dollars ( depending on what mini-laptop you get)
Use a mini-laptop and connect a webcam to it
Connect your laptop's serial port to a motor controller which connects to the motors and stuff
This way your entire platform is wifi enabled and you can control it wherever you get internet . Also you could easily connect a joystick to the computer and control it from there.