Links for DEV-401 prepparation
http://sudheer4sfdc.blogspot.in/2012/03/salesforce-certification-questions-with.html
http://sudheer4sfdc.blogspot.in/  
http://www.proprofs.com/quiz-school/story.php?title=salesforce-certification-dev-401-4
http://www.forceprepare.com/developermock.html
http://www.chicagosfdc.com/salesforce-com-developer-certification-practice-exams/dev-401-developer-quiz-3/
http://salesforce-401-dumps.blogspot.in/2012/09/salesforce-dev-401-dumps-4.html
http://www.infallibletechie.com/2012/07/salesforce-dev-401-dumps.html http://www.infallibletechie.com/2012/07/dev-401-certification-questions.html http://www.infallibletechie.com/2012/07/401-certification-salesforce-questions.html http://www.infallibletechie.com/2012/07/salesforce-401-certification-quiz.html http://www.infallibletechie.com/2012/07/sfdc-dev-401-certification-questions.html http://www.infallibletechie.com/2012/07/salesforce-certification-questions.html
http://www.infallibletechie.com/2012/07/salesforce-certification-practice-exam.html
http://www.infallibletechie.com/2012/07/dev-401-sample-questions.html
http://salesforcedev401.wordpress.com/sf-developer-401-exam/sfdc-dev-401-i/