Trying to find books to use with Kurzweil

I am a middle years Resource Teacher in a 5 - 8 school. My division recently purchased Kurzweil 3000 v12 for all the schools. I am trying to get some of our novels scanned for the program but am thinking that it might be easier to just get ebooks instead of converting these old books. I am wonder if anyone else has gone through this and has any websites that they could share or even anywhere to find free novels that are used in school. I know about Gutenburg and those copyright-free sites but we don't have much call for the "classic" classics in middle years. I would love to have others share PDF books with me and then I can share with others but I don't know if that is allowed due to copyright laws either. Any support or tips would be so helpful!! Thanks.
Donna