Maven

Maven Documentation
http://maven.apache.org/guides/index.html

Sonatype Books
http://www.sonatype.com/books.html

Maven: The Complete Reference
http://www.sonatype.com/books/mvnref-book/reference/public-book.html

Custom Lifecycle
http://www.sonatype.com/books/mvnref-book/reference/writing-plugins-sect-custom-lifecycle.html

Lifecycle Reference
http://maven.apache.org/guides/introduction/introduction-to-the-lifecycle.html#Lifecycle_Reference

Maven Centrol Repository

http://search.maven.org/

# mirrors
http://mirrors.ibiblio.org/pub/mirrors/maven2/jboss/jpl-util/3.2.3/ 
http://mvnrepository.com/