Totalling at £835
Im planning to overclock the i5 to around 4.3-4.5GHz.
It is mostly for gaming and general use/programming, gaming will be games such as BF3 and dishonored at high to very high settings. Where can i save money? Around £140, can i save £100 by buying the gtx 570 and is the water cooling too powerful?
You don't need water cooling.
If you are on this kind of budget, don't go all out with water cooling.
Get a Corsair TX750, also about your ram, get low profile RAM, those heatsinks are useless.
and with your budget, drop the SSD, your build will suffer if you decide to purchase an SSD, SSD's are nice and all, but if your budget is limited, its best not to get it, so you can get the best primary components.