Plain Theme to start from scratch

Hi,

My site will be very simple and plain and does not really fit any of the offered themes. I was wondering if there is a super plain theme which I could use to start building on or if I should use one of the themes and strip everything out or even design my own theme if it is not to difficult?
Either way, I did read the basics and posts about upfront but is there some more comprehensive documentation I can find? Maybe even about theme builder and yes, I did search