Finding Free Building Materials?

I am looking for cheap or free or even donated building materials to help my family and other families. My house is a one story house that has been in construction since I can remember. The room that is suppose to be my mom's, sister's, and mine is covered in black mold due to holes in our ceiling. Our walls are still drywall and our floors are plywood. Our roof is falling apart with a family of squirrels in it.

The other family's house is uneven. One part of their wall has fallen and the windows and doors are torn up. The electrical is torn up and the basement is cement and mud. Their barn which they use as storage is falling apart and the stairs to the basement are hazardous. Please help as much as you can.

By Kt Grace