If you happen to want a nice quick read try looking at one or two of the 'Very Short Introductions'. They're usually pretty well written and can provide a nice little overview of some interesting areas often providing further references. Very reasonably priced too.
- Quantum Theory
- Particle Physics
Also look at Schutz' introductory book on Gravity (not the green GR book!):
Gravity from the Ground Up
See: Gravity From the Ground Up Website
for table of contents, preface and so on.
* Sorry for the .co.uk links!