But in terms of the law (at least the shariah) I've had an interesting time trying to learn more about usul al-fiqh. Right now I'm in the middle of Principles of Islamic Jurisprudence by M.H. Kamali. Unfortunately I was only able to find it free online after ordering it on Amazon. The book goes into a fair amount of detail on how the ulema across different schools of thought derive legal rulings from the Quran and sunnah and the chapters are nicely organized according to various sources or principles. I found it refreshing because it gave me respect for some of the logical and linguistic nuance which goes into harmonizing different texts. It was also comforting to see that local customs, public interest, and avoiding harm are also considered in the shariah and allow it to be more flexible than many people realize.
In case you don't have time to read a 300 plus something book on usul al-fiqh, The Fundamental Principles of Imam Malik's Fiqh from Muhammad Abu Zahrah is organized in much the same way as Kamali's work except it is much more abbreviated and emphasizes the Maliki school's opinion.
Some other interesting pages:
Maxims of Islamic Jurisprudence from Al Majalla (an Ottoman law Manual) gives 100 different legal aphorisms which guide legal reasoning, from a Hanafi perspective.
The blog, Scholar's Pen: The Tools of a Mujtahid- A glance at the Hanafi Methodology gives a brief summary of some of the distinctive principles of the Hanafi school.
While The Principles and Codes of Law of Hanafi Fiqh by Hadhrat Moulana Ashraf Ali Thaanwi is another large book, full of untranslated legal terms and is much less clear than Kamali's work.In fact, these last three sites are all a bit technical and would make much more sense after reading the first two pieces.
Planet Grenada: differences between schools