i had a courier company, at the hieght i had 12 vans on the road and i hated every single minute of it!
i personaly wouldnt pay anybody for information, if you are serious about buying a van, all you need to do is aproach the big boy's, they are always looking for small 1 man bands to run parcels for them.
get yourself down to people like, target,tnt,tuffnels,lynx,etc etc....dont send them letters as they never read them but they may have 5 minutes to have a chat with you!!
i could go on all day!!