What you need is a VPN or Virtual Private Network.
It lets you connect to internet via another computer which is in a different location.
So it seems as if you are in that location to the BBC or ITV
If you were very clever you could leave a computer running at your house in England and then connect to it via VPN
using a free VPN program like teamviewer or something similar.
Otherwise you need to sign up for a professional VPN service.
If you search on google there are many of them.
I use a system called strong VPN and so far it works very well.
They has a package called three cities which costs $55 USD per year.
Here is the link:
http://strongvpn.com/Go to the website choose the 3 city special PPTP 1 year package.
If possible choose a city in the UK as the default location.
After paying by credit card you will go to a screen which has the configuration details.
They have simple instructions on how to install it on most operating systems like vista or xp etc.
If you have a problem there is help via live chat.
Whenever you need to use the iplayer or pretend that you are in the UK just connect to the VPN.
It is also possible to watch American TV if you change cities.
TIPS: If you connect to the iplayer and forget to connect via the VPN it will delete all the saved programs that you have downloaded. For this reason I download them in windows media format and watch the programs using windows media player so it can't do that.
I watched England being thrashed by Germany in the world cup using a VPN connected by a 3G phone. I have an unlimited vodafone contract. If you connect to internet using a phone contract make sure it doesn't cost you a fortune in mobile fees because the downloads are very big.
Links:BBC IPLAYER
http://www.bbc.co.uk/iplayer/ITV PLAYER
http://www.itv.com/itvplayer/