I took the DSST Statistics test in early August. Scored a 78. I used InstantCertOnline.com and CliffNotes QuickReview Statistics.
DANTES Statistics was by far the hardest exam I have taken so far. I hated it with a passion. Even so, I got a 71 on it. So it is definitely doable...even for a math phobic like myself. I bought a Texas Instruments BAII+ calculator for about $30. Knowing how to use the statistics functions was PRICELESS to me on the exam. To study, I used: http://www.instantcert.com http://www.pinkmonkey.com/studyguides/subjects/stats/contents.asp http://davidmlane.com/hyperstat/ http://www.sysurvey.com/tips/statistics/contents.htm http://www.quickmba.com/stats/ Hope that helps!
I used the Princeton Review's Guide to the AP Statistics Exam (can probably pick up for around $14 new, much less used or in an old edition) and passed with a 75. If I remember correctly, you can't take programmable calculators into the exam, but the DSST folks make a list of "approved" calculators available. This test made me really nervous, but is very passable with careful study. Good luck! --Fortunato