German soldiers missing in action-WWI

[ckleisch]

During, the Greatwar I had a great uncle that served with the German Army in Austria-Hungary. He went missing in action in Galicia and was captured by the Russians. My grandmother spent 30 years trying to find him through the Red Cross unsuccessfully. With the opening of Russian records and the advent of computer is there a site anywhere that would list information about captured or wounded soldiers in possession of the Russians and their disposition.