SDL is called Simple DirectMedia Layer and can be used for things like graphics, audio, font rendering, and etc. There are no bounds on what SDL can do. Take a look at the libraries that can be used with SDL. It can be used for many things, not just games. Most SDL tutorials though, if not all, are for game programming, and when you are good enough (I believe in you), you can make SDL work with OpenGL, wxWidgets, and etc.
If you need tutorials, then I suggest(this list will grow over time, if needed):
- Lazy Foo' Productions (I strongly suggest this one for aspiring game programmers)
- SDL at GPWiki (Detailed, but ideally for game programmers)
- DevHub (Starts with object oriented programming)
- Sol::Tutorials (Making a game)
What I suggest is that you actually try to write about what you have learned along with "monkey see, monkey do." Don't copy and paste though. Some parts of the tutorials are mundane, so if you get bored do something else. Stick to one set of tutorials, don't go from one to the other, manage your time, and read articles on graphics (not limited to this subject).
I prefer LazyFoo because it was that first one I actually followed. Believe or not, I do not follow tutorials for very long and tend to stray to other tutorials or not do anything at all, but LazyFoo is the first and not the last tutorial I will follow through. Just toil along and try experimenting, I'm sure you will come to love this little library. :)