Hi, there. I'm happy to share my 2¢.
Going from mid 400s to 700 in a month --- it's possible, if you make a full-time job out of studying for the GMAT.
I'll share some resources. Here's a detailed 1 month study plan I designed. http://magoosh.com/gmat/2012/1-month-gm ... -schedule/
Here's a free Integrated Reasoning eBook:http://magoosh.com/gmat/2012/gmat-integ ... ing-ebook/
You will find that free blog full of helpful articles.
Here's a free video to help you on RC:http://gmat.magoosh.com/lessons/321-gen ... strategies
Here's a free CR practice question:http://gmat.magoosh.com/questions/1339
When you submit your answer, the next page will have the complete video explanation. Each of our 800+ GMAT practice questions has its own video explanation, to accelerate your learning.
I hope all this helps to get you started. Please let me know if you have any further questions.
Magoosh Test Prep