This is from ETS, the company that publishes the GRE:
FREE, official test prep materialsPOWERPREP® II software >
Want to see what the computer-based GRE® revised General Test is really like? Download the only comprehensive test prep that is as close to the actual test as you can get. Experience the new design features first-hand, test-taking strategies, Analytical Writing scored sample essay responses and more.Practice Book for the Paper-based GRE® revised General Test >
Practice with the only simulated paper-based GRE revised General Test created by the makers of the test. You get 1 full-length paper-based test, test-taking strategies, sample questions, Analytical Writing scored sample essay responses and more. A copy will be sent to you once you register for the paper-based GRE revised General Test.
For test-taking strategies and tips for the paper-based test go to ets.org/gre.Introduction to the Verbal Reasoning Measure >
Find helpful advice, sample questions with rationales, scoring guides and tips to know what to expect on this section of the test.
preview Verbal Reasoning Question Types now >Introduction to the Quantitative Reasoning Measure >
Find out what's new in the Quantitative Reasoning section. Plus, get advice, test-taking tips and more.
preview Quantitative Reasoning Question Types now >Introduction to the Analytical Writing Measure >
Find out what's new in the Analytical Writing section. See the entire pool of topics from which your tasks are selected and strategies to help you prepare for this section of the test.
preview Analytical Writing Question Types now >Math Review >
Here's a look at the mathematical skills and concepts that may appear on the GRE revised General Test.Math Conventions >
Learn about the mathematical notations, symbols, terminology and guidelines for interpreting information in the GRE revised General Test.Strategies and Tips >
Get tips to help you do your best on the computer-based test.fee-based official test prep materialsThe Official Guide to the GRE® revised General Test >
From the makers of the GRE revised General Test, this test prep book provides a full-length practice test, hundreds of authentic test questions, explanations for many answers, test-taking strategies, sample essay responses with reader commentary and more. A copy of the POWERPREP® II Software on CD ROM is also included.
view pricing>ScoreItNow!™ Online Writing Practice >
This online service lets you compose and submit essay responses online for scoring, receive immediate scores on your responses to Analytical Writing tasks, review sample responses and general suggestions for improving your essay-writing skills and more.
Interactive Introduction (lecture, interview, polls, transcripts)
We have this book in class in paper form, but you can also get it as a nook-book and read it either on a nook or on your computer. You can probably also read it from an iPad or Android using the Nook App, or possibly from a Kindle.
This one is free:
Free Resources for the New Test
Free Events with Test & Grad School Experts
Grad School Summer Series