os programing book

[nubie]

Hi All,
     I am looking for an operating system book. i came across a book , in pdf format that was like a tutorial about 32 bit os programming, but i cannot remember the name or the web site.  I know i am not specific enough, but the web site also has a paper edition and a pdf one for a really cheap price.I should have taken notes but oh well .  
         If any one knows what i am talking abou please respond. Thanks in advance.
Nubie

[carbonBased]

probably MMURTL
Developing your own 32-bit Operating System
Burgess
SAMS Publishing

Cheers,
Jeff