A website with a bunch of bios introduction, go directly to: System and Component Reference Guide --> Mother Board and System Devices --> System BIOS
A nice introductory article.
The Operating System Resource Center (A great website!)
TinyBIOS: PC Engines tinyBIOS open source BIOS for embedded PC applications
FreeBIOS at Sourceforge
A Site with Bunch of Source Code and Documents
Phoenix (Award)
TinyBIOS: PC Engines tinyBIOS open source BIOS for embedded PC applications