The Foreign Services Institute (F.S.I.) is where the US State Department teaches it's diplomatic team foreign languages.
http://www.fsi-language-courses.com/Arabic.aspx
It has some good materials on the following:
- The Arabic Writing System (PDF) - http://www.fsi-language-courses.com/Courses/Arabic/FSI%20-%20Classical%20Arabic%20-%20The%20Writing%20System.pdf
- A Comparison of Eastern and Western Arabic (PDF) - http://www.fsi-language-courses.com/Courses/Arabic/FSI%20-%20From%20Eastern%20to%20Western%20Arabic.pdf
- Pronunciation of Levantine and Saudi Arabian Arabic.
- A Comparison of Levantine and Saudi Arabian Arabic (PDF) - http://www.fsi-language-courses.com/Courses/Arabic/FSI%20-%20Levantine%20and%20Egyptian%20Arabic%20-%20Comparative%20Study.pdf
This is really good material and I really recommend printing the first PDF about the Arabic Writing System and studying it.
Happy Studying~!