I recently started an in-depth study of the book of Revelation online at versebyverseministry.org. It's quite an interesting series, and so far it appears to be true to Biblical text. It's free and there's no log-in or obligation.
I like that it's available in a choice of video or audio and also provides slides and transcripts in outline form. I appreciate the host's introductory remarks about letting the Bible explain the Bible vs. teaching speculation. And I like how the study brings in interesting points from world history that connect secular history with "His Story" and the history of the Church.
A topical index of studies they provide is on their home page.