Tip: Usually go direct to the horses mouth for the best deals (straight to the network).
And...
Use Quidco:
http://www.quidco.com/ For example, if you were to click through the website listed above (mobiles4everyone.com) they would earn a referral if you then took out a contract with that particular merchant. By going through Quidco you'll earn the referral and pocket it yourself.
So for
Vodafone you'll get a whopping £90 back for just taking out a contract. With
Three you could get up to £80 back and so on and so forth.
