1. Later versions of SuSE should automatically detect your USB ports, but I'm not sure if this was implemented in 9.1. Make sure that your USB modules are loaded first:
2. Install the SWAT package and look at the documentation for it. It lets you configure Samba easily through a web browser.
3. How are you looking for it? Can you ping the Windows machines?
Edit: You should also note that error messages tend to get logged in the file /var/log/messages; first check here if things don't work as expected as it usually gives some clues as to what may be wrong.