thanks guys! zorillo, I didn't study the Princeton or the Kaplan... I am not sure of Princeton, but I looked at some user reviews of Kaplan and the reviews said that Kaplan is kinda tough and the real test is not reflective of what you study in the Kaplan book ( I can't judge on that since I never went through Kaplan book). Also, I didnt want my confidence factor dented. I believe giving a lot of tests is the key. Make sure you practice the Powerprep CD tests that ETS sends. Even though it doesn't tell you what the correct answers are, you get a fair idea of how the real test is going to be. On your question about the amount of time, lets say between 30 and 40 hours... mostly on tests....
rayan, apart from the books I mentioned in my second post, I listened to AM radio on politics, sports, you name it... it helped me a little bit... on the essays, went through the GMAT essay books and picked up a couple of templates that I used for my essay... the structure of the essay is very important. I haven't recieved my essay score yet.. will let u guys know once I recieve them....