Suggested Books

Textbooks

Kochars' Clinical Medicine for Students, Fifth Edition
available at Amazon

Internal Medicine Clerkship Guide, Third Edition
available at Amazon and Half.com

Step-up to Medicine, Third Edition
available at Amazon

Internal Medicine Essentials (released January 2015)
Can get separate textbook and question book or combined online versions.  Note that online access to both books comes with purchase of either book.  Available via the ACP.

Question Book

MKSAP for Students 4
available at Amazon

MKSAP for Students 5
available at Amazon 

IM Essentials Questions (see link above for IM Essentials)

Other Books

On Call: Principles and Protocols, 5th Edition (great for preparing for an Acting Internship)
available at Amazon