Hey Stu - dont stress! Did you get my PM?
Try looking at these sites and start contacting people. I can only offer so much advice as I am in Australia.
www.heathrowletting.co.uk
www.onebigworld.co.uk
www.findaproperty.co.uk
you need to start researching and ringing around. Thats the only way you will find somewhere.
have fun!
craic1510
p.s. If I was based at heathrow I would let you stay with me but i aint. sorry
Thanks for all the advice though.