are you asking if you can get internet via USB on a computer with internet? If so, the answer is no. Unfortunately, the only way to have internet with the iPod Touch is to use Wi-Fi.
I still don't have a wireless connection
What's wrong with using the wifi on either your Macbook or your PowerBook?
You have those connected to the internet via ethernet, right?
Create a wifi network with either of those, and have at it.
System prefs -> Sharing.
Share the ethernet internet connection with users on the Airport.
See this -> Sharing your Internet connection
Also, any reason you still on 10.4.7 as shown in your signature?