Conversion plan

Ah, but a wheel in a bikeshop is likely to cost me well over the value of my bike, which I approximate to be roughly £10, half of which is on inner tubes and break cables.

Racists, always a glib answer.

I'm in Notts, should I be looking for a second hand bike shop..

it's going to be hard to get a cheap fixed rear wheel, but if you look hard, or source the parts your self then get someone to build it, then it might be sort of under £50...