How to tell Auctex where Latex is?

Hello,

I am a total newbie to Emacs and Auctex and I have a silly question but
though I looked at the faq and the manual I cannot figure out, how to tell
Auctex where my TeX is.

To your information:
I am running the Carbon Emacs 21.3.5 on an iBook G4 Mac OSX 10.3 and have a
Latex-installation in /Users/Applications/TexLive2004....

But whenever I try to run Latex I get the message that the process ended
without writing a page.
If I run the same file in TexShop everything is fine and the process ends
without any error.

Cheers,

Joerg Eschenfelder