Homebrew PCBs

Hi All,

I am highly interested in designing my own PCBs with an emphasis on 
eventual commercial products. I am just starting out so I know almost 
nothing about the subject. I would like recommendations on books and 
sources for beginners including web links where I can learn more. In 
addition I would like to hear what software packages you folks are 
using to design your boards. Any suggestions are appreciated. Thanks 
and best regards,

-Dave