Best resource for preparing for the PMP Certification Exam. I would to invest in a tool that would guarantee my passing the exam on my first attemt.

You need to get PMBOK and study from that. Momorize all the terms. Your management expirience might have tought you to think differently but on the test make sure you use PMI ideology. There are several self pased study books for the exam. Look at the sources for some links. There are also many boot camps that make a real difference when you want to take a PMP. They REALLY help.

Nothing can guarantee a passing grade, but if you study enough and memorize their methodology you should be ok.

Good luck.