A quick Google search with "stop cat scratching" offers up many many useful
hits.

Here are some:

http://www.catscratching.com/

   As a checklist, here are the pertinent things to remember:
   1- Don't declaw!
   2- Understand your cat's need to scratch.
   3- Forget punishment--it doesn't work.
   4- Provide a suitable place for your cat to scratch.
   5- Make the scratching post attractive to Kitty-- i.e. use sisal posts.
(Sprinkle catnip on it - Yowie)
   6- Make the place she's been scratching unattractive--physical or scent
related deterrents.
   7- Whenever possible, start cats young.
   8- You may want to trim your cat's claws.
   9- For indoor cats, consider Soft Paws® as extra insurance, or an easy
alternative.
   Dr. Christianne Schelling   Copyright 2008   All Rights Reserved

Or:
http://www.cat-world.com.au/ScratchingFurniture.htm

Or:
http://www.allourpets.com/feline/stop-scratching.shtml

Or:
http://www.catsofaustralia.com/cat-scratching-furniture.htm

Or:
http://www.cozycatfurniture.com/whythecatsscratch.html

Or:
http://cats.consultinghealth.com/article_40.html

Or:
http://www.essortment.com/all/stopcatscratch_rlxi.htm

or even talk to your vet about other ways to train a cat to scratch in
places you find acceptable.

Just a thought: The vast majority of pet cats in the world are not declawed,
therefore there must be effective alternatives to the 'scratching problem'
that the vast majority of cat owners use with success. Otherwise, why would
clawed cats be so very popular as pets?

Yowie
(Mark, if you have time, could you insert this into the FAQ somewhere,
please)