Roaldo has assumed that you want to work for a firm called 'Nationwide'. Since the only one I know of is a bank, I think that might not be the case ;-)
I used to work as a 'trade plater', delivering cars across the country. It meant long hours for fairly low pay but it was certainly an interesting job. I worked for UFD. Their website says that they've not got any jobs currently available but they have a high staff turnover so it's worth an e-mail or phone call to see if they've got anything coming up:
http://www.unitedfleet.co.uk/html/jobs.shtml
Many of UFD's drivers transferred to working for Ace, as they thought the pay and conditions were better:
http://www.acedel.co.uk/
Manheim Car Auctions also employ staff to collect and deliver vehicles across large areas of the country. Contact your nearest auction centre to see if they've got any jobs available:
http://www.manheim.co.uk/find_buy/auction_cent res-b.html
National Car Rentals also have teams of drivers who move vehicles across the country. Use the 'Employment opportunities' option, here:
http://www.nationalcar.co.uk/Content/630/uk/Co ntact-Us/
Hoping something here helps,
Chris