This may be a little off the topic, but I'm considering taking my P.E. test (electrical, for controls, in Oregon) and was wondering if anyone can recommend any good study guides, books, etc.
Well, do you mean Electrical PE or Control System PE? They are two different tests. For EE I would look to IEEE for study material for Control System look to ISA for study material suggestions. ISA publish a book with a complete example test (ISBN 1-55617-476-4). Control System test is usually offered by most state during October with a May/June application deadline. EE is offered April and October.
I took and passed my PE about 4 years ago. My discipline was also control systems. NCEES has study material for other discipline and you can try there at www.ncees.org or the number I called for study material for control systems was 919-549-8411. Again that was 4 years ago and I don't know if it is still the correct number.