I'd just list the books i used and would speak abt them - personal opinions anyway!!!
Kaplan 2006 edition - Very little in the name of theory. They have some strategies too - helpful, but not complete. Each section had 50 test Qs though, which werehelpful to begin with.
Princeton 2006 edition - Lots of theory and strategies - but i wudnt say complete again. More types of Qs covered as compared to Kaplan 2006. Fun to read
Kaplan 800 - One helluva book. You'll be given a bunch of the Qs for each section and all the Qs are from the top draw (or somewhere above it). This MUST be the final book on the prep list. Anyone beginning with this will be SHATTERED
OG 11 - The bible. This is the only place where u get actual GMAT Qs. The prev books are to get familiar with or rather brush up the concepts.
I started with Kaplan 2006, Princeton 2006 and Kaplan 800 in tandem. I'd do one section a week - covering all 3 books. In about a 5 weeks, i was able to finish everything. Now i'm working on OG 11.
I'm doing OG towards the end coz it is better to be in the same zone before the real exam. much of cracking GMAT is abt being familiar with the Qs and being able to think how the test creator wud have thought
About the sample tests - this is my plan. Start with GMATPrep1 and PowerPrep1. These will let you know where u stand. Then strategise ur study plan and frame ur schedule. Work on ur schedule and during this time being do the Kaplan and Princeton tests. They are simply for getting familiar with the 4 hr test. Dont give too much into their scores - they are not supposed to be closer to the actual test scores. Kaplan especially can be pretty demotivating. I havent seen any of the top scores (those who scored 750+ in GMAT) score beyong 670 in the Kaplan tests

One all prep is over, do a GMATPrep2 and PowerPrep2 to see where u need to fine tune and all other stuff.
Disclaimer: Absolutely no guarantee that this will work. Even i dont know as i am yet to give my GMAT

But till date (i've been sticking to this for almost 6 weeks now) i'm doing well and i can see real improvement. What works for me need not work for u
Post if there are any doubts or other queries.
To the GMAT baaps, any suggestions on the schedule are welcome. If you see an scope for improvement, feel free to post in ur comments
Iday