An Avotaynu article by Alexander Beider on Jewish patronymic and metronymic surnames in the Russian Empire has a useful table of given names with some variants. See Avotaynu VII:4 (Winter 1991), pages 12-15.

Dr. Beider's forthcoming work A Dictionary of Ashkenazic Given Names (to be published in 2001 by Avotaynu) will surely be the definitive reference work on the subject.