I'm in medical school now in Chicago.
Bottom line: enjoy yourself while you can. You won't do much good trying to "bone up" and get ahead of the curve by studying course materials. I tried, and several others in my class tried. It doesn't make much difference after the first round of exams. If you can, get some time in clinic, or do some shadowing, to practice speaking with patients.
Spend this time reading about the health care system, about the business and philosophy of health care, and if you have an overabundance of time, read a little history of medicine to get you into the context of what you will be doing.
I find most of the classes pretty manageable, but they require different types of learning. Anatomy is memorizing and visualizing; physiology is reasoning and problem solving; biochemistry is similar to physiology with the added joy of memorizing reaction maps. Most people here hate anatomy the most. Try to get used to studying a lot every day because that's what you will do. Practice putting your own personal desires and vocations on hold for school occasionally, as I often find that I need to put stuff off until school is done.
Buy only the books you are convinced you will use as if they were the Bible. Most everything else is electronic, and class syllabi are generally pretty good. Get a copy of First Aid for the USMLE Step I and begin using it immediately, day one, and build that habit of studying for Boards all along the way. This pays off in spades later.
My most useful books:
Rohen's Color Atlas of Anatomy: for cadaver dissection.
Netter's Atlas of Anatomy. Avoid Grant's atlas, it sucks.
Lippincott Illustrated Review: Biochemistry. It's all you need, period.
Board Review Series: Physiology. The best.
Robbins Pathologic Basis of Disease. Memorize this beast and you'll be king.
Katzung and Trevor's Pharmacology. Drugs.
Clinical Microbiology Made Ridiculously Simple.
Clinical Neuroanatomy Made Ridiculously Simple.
Neuroanatomy Through Clinical Cases.
Other books may be useful or not. Having a Harrison's isn't a bad idea, but it is pricey. Online sources can suffice. The most single useful resource for anything on the fly: Wikipedia. Don't laugh. Everyone, with no exceptions, uses it here for something. Just don't rely solely on it, and you'll be cash.
Psychological considerations weigh more heavily than practical ones for most students. Depression, isolation, frustration, nihilism, and rage are more difficult to deal with than course work. You will love it and hate it. Get a good mentor, someone to talk to and even to vent to, and school will go smoothly.
Get a book, or read up, on the financial side of medical school. I recommend Financial Planning for the Young Physician by Lefebvre, MD. This book has it all.
Learn to bring a lunch to school, it saves thousands a year. Use caffeine sparingly so the firepower is there when you really need it.
Get plenty of sleep. Drink lots of water.
Anything else, PM me. I'd be happy to lend a hand.
Good luck! It is the best profession in the world.
~X