i would say a good way to start off is a canon 300d or maybe a 350d if you want to splash out
you can buy refurbished ones from canon on ebay:
http://cgi.ebay.co.uk/Canon-Outlet-D...QQcmdZViewItem
then a used 75-300mm lens to start off with
or if you have a little more money, look out for a used EOS 10d with some lenses.
i also think sony are introducing a digital SLR, but i dont know much about that one. i'm sure some people will recommend Nikon too, but i've never used one so i cant comment