Love this!  I'm 5th generation Idahoan and all but "hot as a tin toilet seat" are familiar to me - we don't have tin toilet seats in Idaho because you'd freeze to them in the winter.  One of my favorites, from my grandmother, is "wool gathering" as in to day dream or not pay attention.  Another is "up the creek" or "crick" as it's pronounced here - same as "deep water."  Now you've got me started, I'll be thinking of these things for a week!