I think you have a good goal. Anything above 730 would indeed be good for you.
I think you're severely limiting yourself by only applying to three schools. As you know, most schools are only taking 1-5 students... and they get 100s of applicants... more if they're a strong program.
To really have a shot, you should be applying to at least 10 schools... and if you can afford to, 20 applications would be ideal.
Once you've conquered the GMAT, you should post your profile on the PhD Business section of this forum.
personal statement. I used Kaplan and the Official Guide. I think Manhattan or Kaplan would be great... many people have used either of them and scored really well. So go with either, and at that point it's just on you to put in the hours to get a great score.