Jason,
WELCOME TO THE AWS WELDING FORUM!!
On the application form for the exam and seminar there is a section that lists 'Suggested Self Study Materials'. Several good ones among the list.
I also recommend getting the materials that will be supplied at the seminar and studying them ahead of time. Otherwise you are in for a very long week. Lots of reading to do in a short time. I then gave my extra set to my oldest son who is also my shop forman.
I would concentrate on D1.1 as D14.3 isn't covered in the exams in any way.
Have a Great Day, Brent