Since I've been asked a few times I thought it would be easier to do a journal :D
The white background
Firstly, go to Zack Arias's excellent white seamless tutorial http://www.zarias.com/?p=71 as what I do is a variation on this and he says it much better than I do.
I don't have access to or space to use seamless paper where I normally shoot, so I use white bed sheets instead. This leads to several compromises.
The first and major compromise is that it is nearly impossible to get rid of the creases in the sheets so some areas of the background will end up darker than others, in particular the joins between the back, sides and bottom.