How much bandwidth will my customer need to have live video on his website? 1 camera, 480 tvl. He is a new athletic performance trainer, so, his website wont get much traffic.

Live as in what is happening now, or live as in 30 fps?

as in what is happening now. He wants the parents/interested customers to be able to see their kid working out.

You are then talking about live streaming video which you can do cheaply with a webcam rather then with a CCTV system. Anyway ..... it all depends on size of the video and frame per seconds (fps). You can successfully see "what's going on" already at 16 Kbps and 8 fps but for more decent quality I would suggest at least a 100 Kbps at 320x240 using some mpg4 based codec as RealVideo. If you want to get higher resolution keep in mind that an IPcam at highest resolution and 25/30fps will eat about 1 Mbps to provide a good quality.
Are you using a DVR/NVR system ? Are the cameras analogue or IP ?
THX
CIPO