Moar Website Confuzzledness

Ok, so here's my usual website layout:
www.heartofbirth.net or http://heartspark.tezhme.net/

Pretty generic, background colour, header image, repeat image, text layed out in sidebar and main area containers.

Now, what I was *trying* to do, is make the background an image, and make the header and repeat transparent, so the text would appear to be floating on the background image.

I *thought* just making the header and repeat transparent gifs would do it, but noooo.

So how do I do this?

The other option is to use the code from http://eleri.tezhme.net/ and try to figure out how to do that with a new image.