I have a Whirlpool Gold Catalyst Washer that the Agitator will not move. I have checked the Motor Coupler and 1 of the plastic pieces was stripped out and chracked through (none of the ears were broken).

I have ordered a new drive coupler, but have noticed the agitator is locked (will not move).

Any suggestions?

Look here and see what you can learn: https://dl.dropbox.com/u/8010163/Whirlpool%20Catalyst%20Washer%20Service%20Manual.p df
You have a bad problem, I think.