There used to be a wonderfully entertaining book called "Oregon Geographic Names."  Not sure if it is still in print.

You can add Riddle, OR to your list, Brian, and Arock and Lone Rock.  I also like Speece, OR on the UP's branch to Shaniko.  Nothing there except space.

In Massachusetts, where I was born, there are lots of pronunciation challenges: Worcester, Gloucester, Billerica, and names that sound like sneezing - Cochituate, Athabaska and Situate.

Todd Sullivan