International student wishing to join nursing program in US

Hello All,
I am a Science graduate, educated outside of US looking to apply for an accelerated nursing program in Houston, Texas. I have studied Biology upto my high school and then continued with Math, Physics and Chemistry for my Bachelors in Science.

I have the following questions:

1. What should be my initial steps.Is it possible to talk to a counselor for advice on how to proceed in my case or any websites where I can get some info.
2. If I need to evaluate my previous education, who do I contact? Are there any authorized bodies who do this. I had obtained transcript from my graduating college 2yrs back. will it still be valid.
3. How do I go about researching on which colleges or universities to apply.
4. Would the pre requisites differ for me since my education was outside of US.

Looking forward to replies from my fellow hopefuls and respected seniors.

Thanks,
Sanna