As arildno indicated, just click on any typeset string and a popup will appear with the corresponding script.
If you're talking about using LaTeX in more generally than just on these boards (ie. to actually write papers, etc.), take a look at the MikTeX distribution (www.miktex.org)[/URL]. I suggest the Texnic Center IDE if you're using Windows; I've used it for years and have never had any problems.
Or, you can also try this not so short guide to LaTeX. Actually, I find it pretty well-arranged. It contains most things you'll probably need from LaTeX. Just one downside, it's pretty big...