Dedicated server setup

Hi,
I am trying to figure out what it takes to set up multiple servers to where if someone goes to my website URL http://www.example.com it will automatically direct them to the server with the smallest server load on it, without slowing down my website.

I also need help with setting up a third server (all on the same network) that is used for strictly a MYSQL server. many questions such as, which OS to use? do i need to use the same operating system on all 3?how do i tell my script to read the databases on the MYSQL server? and Do i need to purchase a seperate Static IP for each computer? or do i setup one static ip and use a router to assign the three computers their own unique ip? or try to configure them all to use the same IP?

Will mirroring servers make them split the load? or will they both carry the full load ( which is what it sounds like to me "Mirroring")

I know i am asking alot but i pretty much need a complete idiots guide to configuring and setting up all three. as well as some advice on which OS to use? ( i was thinking CentOS 5)

My website will have live timers running on it that must appear on the site regardless of which of the two servers they are sent to. So i need it to somewhat mirror the timers that i setup in my websites admin section so that they are written to the web directories on both servers