And 2 main electronic sources:
DAT question of the Day
DAT Bootcamp.
The above listed were some of the best that I found. The DAT question of the day was a daily email providing a sample DAT question, as well as an explanation for the answer, something that is EXTREMELY beneficial. The same man who made the DAT question of the day, GatorD to be precise, made the DAT Bootcamp Website. This was one of the most beneficial sources, as it provided practice tests for me to use, as well as those extremely important answer explanations. Each day I studied, I would look over the question of the day and the explanation, making sure I understood WHY the answer was what it was.