I was just exploring a link to the Oriental research collection at Oxford University in England. This includes Yizkor books, publications in Yiddish and Hebrew and much more. I do not know how much of the material is available online as I just found the website. hope someone can benefit from this resource!
Finkelstein - Radziwillow, Volin
Bookstein - Ostrog
Lifschitz/Leaf - Rechitsa
Liss/Alper - Minsk, then Pinsk, Odessa, Vilnyas