Here is a reply I provided for another user who wanted to know how to get the solutions to the GMATPrep questions. My advice was to solve it yourself:
The BEST way to learn from them in my personal experience is to print out all the questions you got wrong on paper (1 page per question), staple them together then redo them and solve them yourself. The test gives you the correct answer so you can double check if you got it correct. This challenges you to overcome the mental hurdles yourself (and learn in the process) instead of reading solutions provided by others.
This makes sense right? If you cannot answer the question correctly on paper in an untimed environment with no pressure, how can you hope to answer it correctly on the real exam under real conditions with time pressure?
The last resort is to come here to these forums and search for the GMATPrep solutions. Just about every question in that cat has been covered on these forums so just do a search. But again, I strongly recommend attempting to sovle the questions yourself first - finding the solution should be the last resort.