||Whenever you want to do something and you can't find a tool to do it you might:
1. Search the ESRI Support site generally, Arcscipts especially, the ESRI Developer Network (for samples especially) and the Forums (lots of offered code, expressions, etc. in addition to ideas).
2. Search on different but related terms using Google. Aside from the fact that it may catch something interesting within ESRI, it may catch something useful in all the GIS blogs and other programs that are out there.
3. Check out ET Geowizards, XTools Pro, (both of which have free tools), and Hawth's Analysis Tools (free and being replaced by new free versions).
4. Post to the Forums and ask for help. People here are great.