I am collecting and sharing the books on Sriman Madhvacharya's siddhanta available in Digital Library of India.
Digital Library of India(DLI) - is a huge project where all the ancient and out-of-print books are being digitalized and published without violating the copyright rules.
Accessing DLI - DLI has different centres all over India and some in USA links to some are below.
DLI - Bangalore
DLI - Hyderabad
DLI - Noida
DLI - Ernet
I have over the time downloaded and made PDF documents of some of the books in the below list. If you would like to get the PDFs please email me at firstname.lastname@example.org with the name of the books in the list and I will be more than happy to share it.
Sri T.S. Raghavendran has published about 178 books related to Dwaita Philosophy in English. They are available for purchase from following Website. You can register on the site for free and Look at all the books collections. Books are very reasonably priced and is a real treasure for seekers of Acharya Madhwa's Philosophy.
Sri D.Nagesh Sonde has some of Sriman Madhvacharya's works translated in English. They are good primer to get introduced to Dvaita Philosophy. Recently He has also Published BhagavadGita on his website, which is Moola shloka and Translation of Acharya's Gita Bhasya and Gita Tatparya Nirnaya. You can Check out the books from following site