BigDGeek,
Being charged for estimates by Electricians is not an uncommon thing. Many will do the estimate for free in hopes of getting the work.
Here is a good site for municipal codes in one place,
Municipal Code Corporation. The city listings for Texas are at
Municode.com |Online Library. Many larger cities have their muniple codes online with this provider and you can view them for free.
In this case the City of Richardson WEB site has an online permit process which is located at
Permit Choice (http://discovery.cor.gov/permits/index.jsp - broken link). It appears that Richardson does require a permit for a water heater replacement. You can verify this with the building department and their contacts are at
Richardson TX: Building Inspection (http://www.cor.net/buildinginspection.aspx?id=554 - broken link).
I also apologize for the thread drift about the aluminum wiring. That was referring to the service entrance conductors from your streetside transformer to the electric meter, not inside the home. Aluminum cabling is still used at this point and there is nothing wrong with that. I used to install service entrances and unless requested, and paid for, we installed aluminum exclusively.