I used to use a program called "BAD", and never had any problems with it, but I have read that it could create some really bad results for some people. I still have the original box and floppy, but it may be corrupted by now.
I also have some disk tools from Upper Design, but just reading the package it came in I see that it is for file recovery, not defragmentation.
I would think that there would be many PD defrag programs available.
What kind of problems are you having with ReOrg3.11?