Problems with TexShop for MacOSX
When you first use TexShop, you may see errors along the lines of usr/local/teTeX/bin/powerpc-apple-darwin-current/pdflatex does not exist. or find that TexShop will not edit, compile or create new documents.
The default user preferences in TexShop are incorrectly set, the various paths need to be changed to /sw/bin/.
To change the paths: Open TexShop -> Select TexShop -> Preferences -> then the tab called Engine. Now change all the paths to /sw/bin as shown below, and click on the OK button.