Wired MacPro wont view wireless MacBook Pro on network, HELP!

[xaphonyx]

So i just got a new MacPro and i love it, only problem is i cannot connect to any of my preexisting computers (MBP and MacMini). Iv had a perfectly working wireless network over a Airport Express for about a year, then i buy the MacPro, which unfortunately doesnt have wireless capabilities installed. So i bust out the old cisco router.I have it setup so my cable modem plugs into the router, the router then has 1 cable going direct to the macpro, and another going to the airport express. all of the computers have internet fine, but the wireless cannot talk to the wired. Is there anyway i can make this setup work without buying some kind of wireless usb for the MacPro? any help would be greatly appreciated, Thanks.