In reply to blanchie14c:
I was at the blackpool comp. They just had standard climbing holds, non of the ice things.
I would stick to the carpet method and use the money saved to replace any holds that get knackered by the end of the winter (which I reckon will be not as many as you think).
Also, why not use some small logs (or big ones) to add a bit of dimension to the routes, you can either drill holes into the logs for placing axes or if its a bigger log you can swing your axes into them.
You'll get the idea if you have a look at my photo gallery as there are a couple of tooling comp photos in there.
hope thats helpful.