Hello, and welcome.
For prep material I would suggest the following:
Kaplan Premiere (Good for starting)
Kaplan 800
Manhattan GMAT Books - All math and sentence correction (Highly recommend)
Official Guide 11th ed. (Highly Recommend)
OG Verbal and Math Supplements (Highly Recommend)
While studying for your gmat, I would browse this forum & the knowledge vault, and start researching schools.
Then narrow down on the schools that fit your needs.
After taking the gmat, I would start outlining the essay questions from each school you plan on applying to get a good feel of which school essay questions might overlap one another to get a time plan set up on which schools to apply first.
At this point, I would also suggest that you start to think of people who you can ask for LOR's.
I am sorry if this is to general and all over the place. I suggest reading Montauks book called How To Get Into the Top MBA Programs. I have just started reading it. I won't be applying for another 2 or 3 years for B school, but been researching since Sept. 07 and still learning; however this is a great forum with a lot of people willing to help you get into your dream school.