using one computer to control another - wirelessly

This can be done by remote desktop connection / VNC. However, it can also be done via AppleScript if you like as well.

Apple Remote Desktop is a separate product, however, you can enable in the Sharing preferences to allow remote desktop connections and connect via freeware apps like Chicken of the VNC. This sill allow you to view and interact with the desktop of one machine from the other.

In the case of AppleScript, you can enable receiving Apple Remote Events on the iMac and then control iTunes (or whatever) as you would were it locally. For example:

tell application iTunes of machine "eppc://username:password@some.ip.here"
play playlist "80's Hair Bands"
end tell

Wouldn't it be simpler to allow iTunes sharing on both macs, and then open itunes, and play the shared library?

Did i miss something?

I interpretted his request as asking to control iTunes on the remote computer, not play the remote songs on his local computer. A shared library would permit you to access the music, but you wouldn't be able to control playback on another machine remotely (for example, if that machine was plugged into a stereo system with speakers located located elsewhere).

Perhaps my last post in this thread will be of some help to you?