any recommendations for wills, administrative law, and business associations/corporations?
For admin, one of the people who top-graded the class last year recommended the E&E by Funk and Seamon, but I didn't use it so I can't offer a personal recommendation.
For corporations, people at my school universally recommend the supplement in the Understanding series by Pinto, though he is a professor there so you may want to take this recommendation with a grain of salt. I looked at it a few times and thought that it seemed clear and helpful if perhaps a bit more detailed than necessary.
I have nothing for wills/T&E.