Arduino is great, but it sometimes gets in the way due to its entry level style of doing things. One limitation is making your own library that also includes other libraries.[Scott] has sent in a great tutorial that deals with just that issue.
He covers how to make your own custom libraries while building off of preexisting ones. That’s something Arduino’s automatic magic wont touch.He covers getting your library to compile while including aanother library, linking versus compiling, and getting it all linked up.
Add in clear examples, lots of explanation and a hand full of good practices for C with libraries (like Forward Class Declaration vs Includes, and Using Brackets vs Quotation Marks for Includes), and this is one tutorial that any aspiring AVR or Arduino developer should check out.