Depending on where a person is located, there may be a large amount of local plumbers in the area that can repair most toilet brands, including the Fluidmaster 400 series. Companies such as Roto-Rooter are nationwide and also repair toilets.
There are a few ways that someone can find local plumbers, including classifieds, advertisements, Yelp.com and Angieslist.com. Nationwide companies offer more security and reliability but generally come at a steeper price. Companies such as The Home Depot provide many do-it-yourself classes and even post videos online in which they offer tutorials on how to repair or troubleshoot any toilet problems.