Shoah by Claude Lanzmann is devastatingly good. He only uses footage that he shot himself (so no archival film) of his interviews of survivors, perpetrators, and other witnesses. There's no narrative, but over the course of the film Lanzmann exposes the fear and horror and tragedy that the survivors experience, the excuses the perpetrators deploy to deflect blame away from themselves, and the utter disconnection many witnesses felt from the victims. Among the interviewees are Filip Müller, who had been a member of the Sonderkommando at Auschwitz; Abraham Bomba, a barber at Treblinka and later in Israel (he's actually cutting someone's hair while being interviewed); Franz Suchomel, an SS officer at Treblinka; and Jan Karski, a member of the Polish government-in-exile who tried to convince the Allied governments of what was happening (he was unsuccessful).

Not to be redundant, but this film is devastating.

The Criterion edition is just over 9 hours long.

Look for a writer named Guido Knopp.

Hi! There are a lot of books on the Holocaust on the AskHistorian booklist (link). There's also a WWII section in the FAQ, which has some questions answered on the Holocaust (link) and about a year ago there was a AMA with Holocaust panelists (link).

/r/Documentaries also has a couple documentaries on the Holocaust (link). You just have to skip through the American 'holocausts'.

Hi there. Alas, no one can know "all the details we know about" the Holocaust. There are tens of thousands of books on the subject and about 4000 are added every year (granted, many are not in English). Since you expressed a particular interest in the Sonderkommandos, I'll list some suggestions below. By the way, Sonderkommando means "special workforce" and they were not forced to take part in the killings, only in the cleanup, that is: removing gold teeth from the bodies and burying or cremating them; as well as cutting the hair of the women before they were gassed.

Gideon Greif, We wept without tears: testimonies of the Jewish Sonderkommando from Auschwitz. Yale University Press, 2005: interviews with eight surviving members of the Auschwitz Sonderkommandos

Mark, Ber, and Isaiah Avrech. The scrolls of Auschwitz. Tel Aviv: Am ʻOved Publishing House, 1985: English translations of the secret diaries kept by three members of the Auschwitz Sonderkommandos during the war.

Müller, Filip, Helmut Freitag, and Susanne Flatauer. Eyewitness Auschwitz: three years in the gas chambers. Ivan R. Dee Publisher, 1999: memoirs of Filip Müller who was part of the Auschwitz Sonderkommandos for three years. He also appears in Claude Lanzmann's masterly Shoah documentary, which you absolutely, positively have to watch, as explained by another user on this page.

Chil Rajchman, Treblinka: a survivor’s memory, 1942-1943. London: MacLehose, 2011: very short but very harrowing memoir of a member of the Treblinka Sonderkommandos, written during the war as he was in hiding after his escape from the camp. If you want to get a raw, uncensored feel for what life as a Sonderkommando member was really like, read this.

Arad, Yitzhak. Belzec, Sobibor, Treblinka: The Operation Reinhard Death Camps. Indiana University Press, 1999: Still the best single volume study of the lesser known death camps where more Jews were killed in the gas chambers than in Auschwitz.

Langbein, Hermann. People in Auschwitz. Univ of North Carolina Press, 2004: the most accessible single volume study of Auschwitz, by an author who is an Auschwitz survivor himself.