Just a quick update for those that helped or were interested.
I phoned Phil yesterday and after 10 minutes on the blower almost everything was sorted bar a couple of quick checks. Below is the system (roughly) that I ordered.
Case: Antec P182 Advanced Super Midi Tower Case Gun Metal Black
CPU: Intel i7 920 2.66GHz 4.8GT s QPI 8MB Cache Retail
CPU Coolers: Thermalright Ultra 120 eXtreme 120mm Heat Sink Fan
Overclocking: 3XS System Core-Logic Overclocking*10 - 20%*
Memory: 6GB (3x2GB) Corsair XMS3 DDR3 PC3-12800 (1600) CAS 9-9-9-24
NVIDIA Graphics - Multi GPU SLI Options Available: 1GB XFX GTX 285 Black 690MHz GPU 240 Cores 2600MHz GDDR3
Power Supply Unit: 620W Corsair HX Series Modular PSU (Single Graphics Card)
System Drives: 1500 GB Seagate
Floppy Drive Flash Card Readers & Writers: Akasa Multi Memory Card Reader & USB 2.0 Port
DVD Writer: Pioneer DVR-216DBK 20x DVD±R 12x DVD±DL DVD+RW x8 -RW x6
Blu Ray Reader Writer: LG GGC-H20L - Super Multi DVD Writer & Blu-Ray + HD-ROM Reader
Sound Card: Creative Sound Blaster X-Fi Titanium Sound Card 7.1Ch
Operating system: *Operating System Not required* (System Tested under Microsoft Vista)
Extended Warranty: 1 Year Scan Extended System Warranty (£1001 - £2000)
I also then did quite a bit of research and found this beauty of a KVM switch.
I'm sure that there's bits that I customised I've forgotten, but that's the core.
The big decisions were the case and the Graphics card. I went for the case because Phil really recommended it and it offers very good levels of quietness. They only had 1 left in stock - so good job I made my mind up when I did. And on the Graphics card.... Well I didn't want to go SLI, so I simply went for the fastest thing out there based on a single card solution.