Lucasbananas: I think you can also use a USB installation stick (which I presume you used to install Ubuntu on your netbook) as a repository, but I'm not sure how. You might be able to find instructions via Google.
What you definitely can do, however, is download what you need from http://packages.ubuntu.com/lucid/build-essential At the bottom of the page there are links to the actual downloads; you need to select the appropriate one depending on whether you have installed 32-bit Ubuntu (i386) or 64-bit (amd64). It will then send you to a list of mirrors; click the link for a mirror close to you and you'll be able to download the file you need.
You also need to do the same for each of the packages listed as dependencies of build-essential, i.e. dpkg-dev, g++, etc.
Once you have all of these files, which should add up to about a half-dozen .deb packages, transfer them to your Ubuntu computer and save them on your desktop there. Then open a terminal and run the commands:
This will install all of the packages. After that, you should be able to compile the driver using the instructions in post #6.
sudo dpkg -i *deb
Alternatively, you could also just upgrade to Ubuntu 10.10, which should support your hardware out-of-the-box.