The only way to move stuff from your Mac Pro to the Touch is through the iTunes software.
As far as I know, you cannot use the Touch to access files on another computer in the same way as you would if you used another computer.
OK I'm having a brain block with this. I would like use the wifi of my iPod touch to access stuff on my mac pro. I don't have air port so I wonder if I can buy a third party solution and if I do, do I have to buy a cable modem, or can I just get some thing that plugs right in to the mac pro.