I did a couple of Google searches and found incomplete references to a Frank Herbert Museum in Tacoma, WA. Here's one, you have to scroll down for the comments:
http://seattlemetroplex.wordpress.com/the-emerald-whistler/
"And don’t miss the Frank Herbert-Museum. Good old Franky was a science-fiction author in the 20th century, known mostly by his epic Dune-Trilogy, and one of the famous sons of Tacoma."
Does anyone have any more information about this?