The following is from PASTA website

<pasta>
Free Edition

A free edition of the Package Structure Analysis Tool is no longer available for download. This edition is fully functional, except that the functionality to refactor the source has been disabled. A full version is part of the OptimalJ suite.
</pasta>

However, PASTA has been superceed by "OptimalAdvisor"

http://javacentral.compuware.com/pasta/whatisnew.htm

There is a free version of OptimalAdvisor. I have not tried it yet but I will try the latest version as soon as my registration goes through.