I borrowed the Kaplan book from one of my friends, and found it to be the best source. I just read it twice over, but didn't memorize anything really. Personally, I think the course is a waste of money, because I studied on my own using Kaplan and Barron's, and got a pretty good score on the DAT. I didn't use TopScore, because I didn't know about it, but it seems like everyone recommends it.
Therefore, it can be done! And cheaply at that!