http://www.williamhua.com/2009/04/git-and-repo-for-dummies/
http://www.blogjava.net/sxyx2008/archive/2011/04/11/348071.html
官方：
http://source.android.com/source/downloading.html
下载并编译
http://w11h22j33.iteye.com/blog/891456
2.2 2.3 源码下载
http://rgruet.free.fr/public/