http://mobile.tutsplus.com/tutorials/android/ndk-tutorial/
http://marakana.com/forums/android/examples/49.html
( i implemented the code from this tutorial. it went on pretty smooth… its in https://bitbucket.org/mzsrtgzr/ndkdemo)
http://marakana.com/forums/android/examples/96.html
nice how to pass object from java to c and vise versa:
http://www.steveolyo.com/JNI/JNI.html
access java classes from ndk
http://bertleung.wordpress.com/2010/06/11/access-java-class-variables-from-ndk/
http://timecubepuzzle.blogspot.co.il/2012/05/development-on-android-ndk-gluing-c.html
nice beginner tutorial:
http://mhandroid.wordpress.com/2011/01/23/using-eclipse-for-android-cc-development/
http://mhandroid.wordpress.com/2011/01/23/using-eclipse-for-android-cc-debugging/