I downloaded these books from the Delhi University DSPACE website.These cover the history of Vijayanagar,muslim invasions of South India etc.I will add more books to the list from time to time.
1.South India and her Mohammedan Invaders: written by KAN Sastri who was a pioneering historian of South India.
South India & Her Mohammedan Invaders
2. Early Muslim expansion in South India :
3. Sources of Vijayanagar History
4.Vijayanagar Sexcentenary Commeration Volume
5. Studies in the Third Dynasty of Vijayanagara
6. Mediveal Jainism With Reference to Vijayanagara History
7. Social and Political Life Vijayanagara Empire Vol I ( AD 1346-AD 1646)
8. Social and Political life in Vijayanagara Empire Vol II ( AD 1346-AD 1646)