Hi Kim -- first, congratulations on inheriting a home! Sorry to hear you are dealing with the need for home repair and maybe mold. As far as I know there is no single place where you can go and apply for a grant for home repair. However, there are a couple of resources you can try, and one of them is pretty new.
The first place to start would be your local HUD office. You could search for "HUD agency" and the name of your city, county or state to find the closest one, or call 1-800-569-4287. This is the federal Housing and Urban Development department, and depending on where you live there may be grants available to help you, especially if the problems with your home make it an unsafe or unhealthy place to live. There is also a new program called NeighborWorks. It is a nonprofit created by Congress to help homeowners in low income and middle class categories. They operate through a network of organizations across the country and may be able to refer you to someone who can help. To locate the program nearest you go to the NeighborWorks website and click on Our Network at the top and then on Network Directory. Then you can enter your state and/or zip code and see what it near you.