Where can I find a guide to Terminal Commands?

Have you tried Google?

 

It kind of depends what you want to do.
There are really advanced topics, but there are also some simpler things.
A article that simples some simple topics is: http://newsourcemedia.com/blog/basic-terminal-commands/.

 

What you want is a book on unix shell programming. The oreilly book "Learning the bash Shell" is decent.

When you run terminal you get a unix shell. Most likely the shell you're running in is called the bash shell. It might also be called sh, but the two are similar.

Open up a terminal and type the command:
ps
The right column in the output will tell you what shell you're running. That's the subject you want to learn about.

 

A good place to start.

Ryan, you may have found something already but a good place to start can be found at this address, <http://www.gnu.org/software/bash/manual/bashref.html> It is a very comprehensive reference for the bash shell. Cheers.