Huge thankyou to you all, you have helped me enormously with this.

Preston, the idea of renting some equipment is great - I hadn't thought of that atall.

Sunstruck - I have been looking at the SB900 and from what you all say that's the way to go. The SB800 is difficult to get hold of now and the difference in price isn't huge. I would rather invest a little more if it puts me in good stead.
Sunstruck and Kelly - really really useful advice on the lenses - I need to build up my kit and will go and price these up.

Once again, thankyou so much everyone, I can't believe how much feedback I have got on this
I will post a couple of photos of my work later as I must rush off to work now!