http://cdis.missouri.edu/
Call your state department of education if you are in the United States. They should be able to tell you where to look.
Try these, www,agora.org or free library.com paleainersonline.com hope these help.
HS Mom has a good list there - I support those suggestions, as well as trying WorldWide IDEA Private Academy - http://www.worldwide-idea.org - they are an accredited virtual school for homeschooling families. If you are in Idaho, try http://www.idahoidea.org.
K12.com or ChildU are really great ones. Look them up to see if they are in your state.