Software :: Git Configuration / Git To Remember All The Changes To (CURRENT_FILES) But To Not Keep A Copy Of (REMOVED_FILES)?

I have a folder that contains a bunch of source code tarballs and some shell scripts that compile it all. I've been using git to keep track of it all. It works very well. It makes it easy to distribute recent changes to the computers I look after - just git pull and all the recent changes are updated without me having to remember everything or redownload the whole thing.

The problem I have is that when I update a package (eg gnumeric-1.8.4 => 1.10.0) git keeps a copy of the old tarball so the whole repository grows ever larger. At the moment the only solution I have is (when the folder gets over 3GB) to delete .git and start over. This is less than ideal, I want git to remember all the changes I've ever made to the bash scripts so that I can go back and review the code, but I don't want it to keep a copy of all the old tarballs. ie, after I've used git rm ${FILE} it should delete its backup copy of ${FILE} but I still want it to keep track of all the changes to the current files (the bash scripts never get removed, only changed)

How do I tell git to remember all the changes to ${CURRENT_FILES} but to not keep a copy of ${REMOVED_FILES}