You'd think an enterprising IE out there would be able to engineer a competent guide to use for keeping up on those skills we learned in school. I have never seen a book that really does the job.
IIE sells a PE review book by Young and Kennedy. It's not bad. But it is also not good. Unfortunately, since it is the only IE PE review book out there it is all you've got in that department.
There are also the two Handbooks:
Maynard IE Handbook
Salvendy IE Handbook.
I have them both and both provide a wealth of information in a format so voluminous and verbose that they are a headache to use. They look good on your bookshelf though. :-)
My advice is to download the IE exam specs at NCEES. Look at the subject matter breakdown and plan your own route to competency in those areas. Use your old textbooks because there is nothing out there better (for those still in school sell back your non-major texts but NEVER get rid of your IE books!) Buy new texts for subject areas you do not already have books for.