Needed PHP/MySQL guru

I have a website that I'm ready to launch. It is built on PHP/MySQL on Redhat Linux. I am satisfied for the most part with how it works. However, the site runs far too slow and MySQL cpu usage jumps to 40-50% with every click. I'm looking for a performance increase, which I will test with some basic load and stress testing tools. The website is on it's own server, so I doubt it's a hardware problem. I am looking for a PHP/Mysql guru to fix the speed issues and possibly work on additional features. to begin work, you will need to sign a non-disclosure agreement. In your bid, you must include 1) the url of a website you have worked on, 2) how many visitors visit it in a given hour or if it's been load tested before and what it's rated capacity is and lastly 3) how large/complex the database is. Feel free to show off your work and convince me you are the best person for the job. I imagine you will probably have to redo some of the php pages and rearchitect the database, so i'm looking for someone who has experience with this. References are important, so if you've done great work in the past, please allow me to contact them for more details. Payment will be via Paypal or GAF and will be made after project completion and I have tested it and seen a sizable performance increase. This is to insure I do'nt get bidders who fail to deliver and want to waste my time.