cDNA from blood - protocol

[Soenke Behrends]

Dear netters,

do you have a good protocol for isolating RNA / cDNA from 
whole blood. I am not after a special kind of white blood cell
since it is anyway only hope that my mRNA is expressed in 
any blood cell. However, i want to investigate a special individuum
where I cannot get anything else than blood. 

Any hint regarding protocol / critical step / commercially available
kit would be of great help. 

Thanks for your time and help
Soenke