Here are some of the most important digital sources for Jewish genealogy researches in Baden-Württemberg.
(But first of all you should know in which places your ancestors lived, without knowing this you can't start your researches.)
Standesbücher Baden-Württemberg (Birth, Marriages, Deaths, Cemeteries, family registers)
Photos and Inscriptions of Headstones of all Jewish Cemeteries in Baden-Württemberg
Military Records of soldiers of the Württemberg Army in WWI (Militärische Bestände)
(You need to know which regiment and company your ancestor was a part of.)
Military Records of soldiers of the Baden Army in WWI and some
other digital documents of the Generallandesarchiv Karlsruhe
Jewish Comunities, Synagogues, Cemeteries (History, newspaper Clippings, Photos)
Many German Cities commemorate the Holocaust victims (not only the Jewish ones) with Stolpersteinen.
For most of the people mentionned on the Stolpersteine extensive researches about their life and family were done.
And I remember that DigiBaeck has some of the Deportation Lists from Baden to Gurs and reports of witnesses.