[CentOS] TrueCrypt WD External Drive

I have a WD Elements 2TB USB hard drive.  I would like to
encrypt the whole drive with TrueCrypt on my CentOS box.
Could someone direct me to a tutorial on how to do this?
Ideally, I would also like to access it with my WinXP box,
but this part is optional.

Thanks for your help.
Mike.