with linux you can run programs from the command line(type in name and hit enter) and they will run, even graphic ones
Often times when you install an app it wont put a shortcut in a menu or an icon on your desktop, you have to do that yourself.Some GUI's dont have icons or shortcuts, mine doesnt.
Go here:
http://www.tldp.org and start reading, I believe they have some tutorials as well ALL docs on linux.You can also find docs on the software in your system in /usr/docs