I have finally have a smart phone!
My existing unsmart phone SIM on contract could not easily update to have data with O2. O2 would have been happy for to get a new SIM only Contract which was going to cost me a lot more on my monthly payments.
My solution was to move to GiffGaff!, owned by O2 but run as a seperate company. They have some very good SIM Only phone Tariffs.
They have some good links for free to fairly cheap phone unlocking. I paid £3.99 and phone unlocked within minutes.
Good deal on Blackberry SIM's and Blackberry Internet Services.