Which part of Germany does the surname FILLMANN originate from?

Question:

Which part of Germany does the surname FILLMANN originate from?

I have a relative of that surname who came from Germany somewhere and I am trying to narrow the field.

Best Answer - Chosen by Asker: This site suggests it is a Southern German name: http://www.ancestry.com/learn/facts/fact...

This particularly family's site also seems to back that up:
http://members.aol.com/esfillman/researc...
Heichelheim seems to be a popular location but that might just be this one branch.