I found Daniel V. Schroeder's Introduction to Thermal Physics
an engaging and accessible introduction to both thermodynamics and basic statistical mechanics. I'm surprised to see so many Amazon reviews
panning it, though some make the good point that it may not be best for self-study since it doesn't include answers/solutions to problems.
Of course, should you run into trouble with anything in whatever text you end up checking out, you know you can bring it to this site for help.