You don't necessarily need to know what model the keyboard is; it's usually possible to detect what keypress signals the buttons send and work from there (assuming the keyboard driver detects the extra keys properly).
You basically have two options:
The easy option: install
lineak and it's gui configuration tools. Use those to set up useful commands for the keyboard. Lineak is easy to use, but you'll have to live with a small daemon program running in the background all the time.
The slightly more complicated option: Configure xmodmap to recognize those buttons, as explained
here. It's a bit more work to set up, but you don't have to have any external programs or such running.
There are a few more options out there, but most of them aren't worth your time, in my opinion. These two are enough to do the job. Note that you may not be able to set up the keys to do exactly the same things they did on Windows, but at least you'll be able to use them for something useful.