Hi...
Here are some of my favs for Step 1:
First Aid (yep, a MUST)
Biochem: High Yield and Lippincotts (detailed so use it during your course)
Micro: Made Ridic Simple and High Yield
Pharm: Lippincott's and High Yield
Path: BRS and High Yield (you'll undoubtedly see a trend here
)
Anat: High Yield or Ridic Simple
Behavioral Science: didn't use one (have a couple of degrees in it) but others recommend High Yield
Molecular Bio: High Yield
As you can see, I used High Yield series a great deal. However, these are for REVIEW not as primary texts, so you must have others to supplement (usually your course texts).
For a good review which I've found on target, look at
http://www.medschool.com Book Reviews.
Bestof luck!