Dear Terry ur q is not clear here. Internet means what kind of internet. either data card or broadband nor any voice modem ? Actually, in SuSE Linux there r many ways to start Internet.
1. WVDIAL 2. Kinternet 3. or any 3rd party software.
If u r using wvdial to connect then just press ctrl + z to terminate it.
If u r using Kinternet, there is a icon on Taskbar / Panel. (Looks like plug) just right click and close it. Or if u r using any 3rd party sw then there is a mechanism to stop it. I don’t know, will this answer help u or not….