My last name has officially changed

I have legally changed my last name. It wasn't too bad - only $10 and about 3 hours of my time on a Friday afternoon. Now comes all the phone calls and letters to credit card companies, banks, magazine subscriptions, bill companies, etc. letting them know about the change. How long will it take to get everything switched over - probably years!! At least that will give me enough time to learn how to sign my new name!!