prevent doubleapple files creation when tarring directories (Snow Leopard)
@LauriRanta answered the question by giving two solutions. 

The first solution is to use COPYFILE_DISABLE=1 tar -cf directory.tar directory each time you want to tar a directory without the hidden files.

Her 2nd solution however - and also the one I was looking for - shows how to automate the whole lot by using an alias. If you don't know what an alias is (I didn't) there is a great tutorial available here that shows how to create a temporary alias (only valid for current session) and a permanent alias (stays valid even after turning your Mac off).

I used Lauri's suggestion with a few additions to create a permanent alias:

alias tarc="COPYFILE_DISABLE=1 tar --exclude '\\.DS_Store' -zcf"


so next time I want to tar a directory without overhead I only have to write tarc chosen-gzipped-tar-filename.tgz name-of-directory-i-want-to-tar/ and beam it up to my webhost.

Thanks for all comments and input!