I have spent the last couple weeks starting to write my thesis. This is normally fairly easy in Word, just start typing and format later. In LaTeX its the other way around. Format first and then write, you'll save yourself loads of time and headaches at the end. I last used LaTeX for my honours thesis and have mostly forgotten the commands.
Andrew nobly pointed out a thesis template from UCLA that is very handy but not terribly well documented. I have eventually got set up and realised that the reference formatting in the text is somewhat bizarre. I have now switched back to abbrv until I find out what the UCT standard is. You will also need to add the amsmath and graphicx packages
A really helpful resource is Andy Robert's LaTeX Starter Guide which contains nearly everything you'll need to do maths, tables, figures and formatting. It even includes a comprehensive list of symbols so people like Raoul don't have to search all day for the infinity symbol :P
Editor-wise I am writing in TexShop, a Mac program and using BibDesk to store my Bibtex references. If you're in Windows I'm told that MiKTeX is very nice including a file structure sidebar and JabRef for reference editing. For those of you who break out in hives at the thought of learning a new markup language, try LyX, I've heard wonderful feedback about it.