Soori,
I followed the following things,
Mark Cade - Certification Guide
Paul Allen - Certification Guide
Set of questions from SCEA_PREP groups
Three hours preparation per day was enough for me...
I had to spent 4 weeks for the entire preparations...
Mock test is very very important one.. we can easily estimate ourself...
how fast & how far we are in the preparations...
All the best for your preparations.....