Have a look at this site. They claim to supply most of the trade so their prices are a very good starting point.:
http://www.totaldigital.biz/default.php
There are not many plasmas as small as 37" and those that are are normally Panasonic(I have one). Here is one for only �899 from the above company(which is based in Brum) but it is a wall mounted version which in fact I have(wall mounted that is not this model):
PANASONIC TH37PD60WAL PLASMA TV XGA Panel Built-in FREEVIEW DVB
So you need to sometimes factor in costs of wall brackets )or stands but not always as they can come included for the price as in the offer above
You need to bear in mind with sites like pricerunner the delivery charges. Also take into account how many years guarantee a product has from that company.
Hope this helps.