Where can I get an iPhone 4 cheapest on contract?

I'm looking for an iPhone 4 (possibly 4S) on contract with a minimum of 200 mins and unlimited texts (and maybe internet if possible). I know this is a lot to ask but can someone find it for under £20 a month for 24 months or less (you can still tell me if it is higher then 24 months but try to get below).
If you find a deal for me for £25 or under, tell me about that too. Can it also be under £50 to pay for the phone.

The iphone 4 is free with a contract from verizon so just get a cheep contract

ChitterChatter runs on the t-mobile network. They are offering:

iPhone 4 Price: Free
+ 2000 minutes to any network
+ Unlimited texts
+ Unlimited T-Mobile calls
+ Unlimited internet/data on your phone

£26 per month
24 month contract

Its Way cheaper just to buy the phone without any sim card, then get a cheap contract sim that will give you what you want. The sim won't fit so you will have to cut it to shape, but I did ths and trust me it works way better. Check out these websites:

For the phone- £299
http://www.amazon.co.uk/...003TQ3NCY/

Sim
http://shop.orange.co.uk/mobile-phones/sim-only/pay-as-you-go#

and cutter
http://uk.cellphoneshop.net/5sim.html?adtype=pla&cagpspn=pla