Hi Tariq,
Yes, if you don't need a MBA online with no GMAT then you can double your choices by looking at all program options.
My friends tell me the best free GMAT test prep software comes from the people who make the administer the GMAT itself. GMATPrep software practice tests are free to registered users of mba.com, GO:
www.mba.com/the-gmat/download-free-test-preparation-software/ This free software will help you prepare for the GMAT® exam.
GMATPrep software uses the same technology as the official GMAT exam so you can simulate the actual test-taking experience. By doing this you will see if there are weak areas you might want tutoring on or more expanded review of on the exam.
The GMATPrep software features:
90 free questions – 30 Quantitative, 45 Verbal and 15 Integrated Reasoning - with answers and explanations
Tools to create your own practice set
2 full-length computer adaptive practice tests with answers
Accurate computing of GMAT® Total, Verbal, Quantitative and Integrated Reasoning scores, which you can use to judge how prepared you are for the actual GMAT exam
A comprehensive math review
A step-by-step guide to preparing for the GMAT® exam
If you LIKE the free experience you can purchase from them upgrades to get more of the same.
How long you should study for the GMAT will depend on the results of the pratice tests. These tests will help you diagnose where to focus for more your test prep --- if you need it. You may do so well on the practice tests your scores will be decent enough to take the real exam fairly fast.
Good Luck!
If you find other good resources let us know.
Vicky