Ever since I finished IDP (now AXP) and began to study for the AREs I've been hearing about Caroline's Notes and have seen them on many people's desks. She created her notes using study material from the Kaplan 2011 Study Guide, the second edition of the Ballaset ARE Review Manual (which I'm also using to study), and the AIA Contracts (of course, I'm also using this necessary study resource). It is a great collection of notes, but is by no means all-inclusive. As others suggest, one should read any and every source available, from Ballast to the Code Book to the CSI MasterFormat list.
The A series contracts deal with the General Contractor, except for the A201, which describes the a lot of the rights and responsibilities of all three parties: the architect, the owner, and the contractor, and their relationships with each other.
A101 - Owner + Contractor Agreement
A201 - General Conditions of the Contract for Construction
A305 - Contractor's Qualifications Statement
The B series contracts deal with the architect. The primary B series contract for the CD+S exam is the B101, although test takers should probably also be aware of the B102-B109 contracts (additional services or different scopes) and the B305 (Architect's Qualification Statement)
B101 - Owner + Architect Agreement
Feel free to write me and correct me if I'm wrong, but from my understanding the G series contracts deal with both the contractors' bidding process and the construction process. The contracts below, which are the primary G series contracts to study for the CD+S exam, are all to be used during the construction process, but other G series contracts like the G716 (Request for Information) and the G804 (Register of Bid Documents) seem to deal with bidding.
G701 - Change Order
G702 - Application and Certificate for Payment
G703 - Continuation Sheet
G704 - Certificate of Substantial Completion
This is the best practice test I've taken yet, and has the most comprehensive descriptions of the correct answers afterwards. It's also helpful that it's timed, similar to the real thing.
It's nice to have some questions and a study sheet directly from NCARB themselves...
PDF from NCARB
It's nice to have all seven divisions of the 4.0 ARE in one book. I purchased the 2nd edition Ballast book before the announcement of the switch to 5.0 (and now realized how much I've lagged testing) but the book contains a lot of study material on three exams that transfer to 5.0 when they're grouped, and count as four exams in 5.0.
This PDF follows the life of a building from the owners collection of site information to the completion of construction, and covers the various methods of project delivery. It covers addendum and contract modifications and goes all the way through substantial completion to project close-out. The only problem with this file is that the contracts referenced seem to be the older, 1997 contracts (like the B141).