In reply to Captain Gear:
What car is it?
If finding a blank is the problem you can usually find them on E-bay.
Older fords have a clip-on/off bit with the fob so you can just cut a new key and clip the original fob on if you damage a key.
When I needed a new key I went to timpsons and they quoted my £75 then went to a place in my local morrisons in Sheffield and got one for £44, including programming the chip.