Any help with my build Please

Any help ?

Looks like you are planning to over clock your CPU? If so, you will need a better than stock cooler. Something like the Cooler Master 212 evo for a slight over clock will work. All your components will work fine together, the PSU is a bit over kill, but it allows for another gpu later. And I think you meant 3570 on the CPU, is that with or without the K? If you can add a SSD, I think you would really like it, But it is not necessary.

If you're not going to overclock you could cut down on the motherboard and CPU and save some money:

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-3350P 3.1GHz Quad-Core Processor (£136.52 @ Dabs)
Motherboard: ASRock Z75 Pro3 ATX LGA1155 Motherboard (£70.72 @ Amazon UK)
Memory: Corsair Vengeance 8GB (2 x 4GB) DDR3-1600 Memory (£38.99 @ Overclockers.co.uk)
Storage: Western Digital Caviar Blue 500GB 3.5" 7200RPM Internal Hard Drive (£41.00 @ Ebuyer)
Video Card: Club 3D Radeon HD 7870 XT 2GB Video Card (£171.62 @ Amazon UK)
Case: NZXT Source 210 (White) ATX Mid Tower Case (£31.18 @ Scan.co.uk)
Power Supply: Corsair Builder 600W 80 PLUS Certified ATX12V Power Supply (£54.98 @ Novatech)
Optical Drive: Lite-On iHAS124-04 DVD/CD Writer (£12.98 @ Scan.co.uk)
Total: £557.99
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-02-20 18:12 GMT+0000)

I would get the xfx psu over the corsair cx, it's a quality psu made by seasonic and it's cheaper, and has better capacitors, the cx series is the entry level series of the corsair psus, also you don't need 750W, a 500W psu will do, the 7870XT is a better option that the 660 gtx, since it's a better card for the same price, that case is decent, but the corsair 200R offers quality and good cable management for less.
You don't need the z77 motherboard for a locked cpu, the asrock h77 pro 4 mvp has everything that you'll need and the i5-3470 will have the same performance as the i5-3570, both with the igp.
Since you have a hdd and dvd drive, get a ssd with 128GB.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-3470 3.2GHz Quad-Core Processor (£145.62 @ Aria PC)
Motherboard: ASRock H77 Pro4/MVP ATX LGA1155 Motherboard (£68.87 @ Amazon UK)
Memory: Corsair XMS3 8GB (2 x 4GB) DDR3-1600 Memory (£32.99 @ Amazon UK)
Storage: Sandisk Ultra Plus 128GB 2.5" Solid State Disk (£69.96 @ Amazon UK)
Video Card: Club 3D Radeon HD 7870 XT 2GB Video Card (£171.62 @ Amazon UK)
Case: Corsair 200R ATX Mid Tower Case (£46.99 @ Aria PC)
Power Supply: XFX 550W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply (£48.17 @ Aria PC)
Total: £584.22
(Prices include shipping, taxes, and discounts when available.)

The ssd is out of stock in amazon uk, but in the link of the product, there's other shops selling(dabs) it for about the same price.
Review of the card : http://www.overclock3d.net/reviews/gpu_displays/club_3d...
Performance summary : http://tpucdn.com/reviews/Club_3D/HD_7870_jokerCard_Tah...

Yeah, the only advantage you get with the 3570 is either if you are using its graphics chip or if you get the 3570k for overclocking. If you aren't overclocking, stick to the cheaper CPUs because you'll get the same performance out of them.

I wont be Over clocking but it was the 3750k i was going for - i was thinking having the 750 watt psu encase of any upgrades ?

If you don't plan to overclock the i5-3470 will suit you, it will have the same performance as the i5-3570k at stock, the xfx 550 core edition will do for any single future cards that might come up(even for the geforce titan), it has amps/juice for any single high end gpu(single gpu on the pcb).

What is a good MoBo which will support the i5-3750k and i5-3470 and that can support 2 GTX 660 as i plan to do future upgrades also i was thinking of getting inwin Dragon Rider White Full Tower

This board supports SLI : http://uk.pcpartpicker.com/part/asus-motherboard-p8z77v...
But i would get a better card now, like the 7870 tahiti le or 660 ti, instead of spending in a more expensive board, the corsair 200R will do for two cards, it's a quality case.

So what parts would you recommend me getting if you could do me a list , I would much appreciate it.

Did you checked the list that i made above ?
The list : http://uk.pcpartpicker.com/p/EMeW
you can ditch the ssd and get a higher end card : http://uk.pcpartpicker.com/p/ENij

Or if you want to SLI : http://uk.pcpartpicker.com/p/ENgF

Plenty of options there.

Cheers for all your help , Thankyou !