Immigration experience
About 10 years ago I was in your position too. A little advice: don't be scared to death by INS, stay strong. The thing that helped me the very most was a book I had my bookstore order for me called "How to Get a Green Card: Legal Ways to Stay in the U.S.A." by Attorney Loida Nicolas Lewis & Len T. Madlansacay and published by NOLO press. The book was so good that my Immigration Lawyer was reading it. He cost me $1200.00, the book was only about $12.Nolo's web address is
http://www.nolo.com and search for their immigration law resources. Things change as quickly as the congress changes so what is the law now may be an amendment in 3 months. Hang in there and remember you are a US citizen and have the right to marry who you choose. I would be careful about talking too much with friends about your situation because they won't understand and after so many warnings of "be careful, you know those people only marry you to get their papers and then they leave", you began to get very depressed. So talk about it with people who are in a position to help. Get the applications filled out carefully and completely. Go over them several times before you mail them in and most importantly, DO NOT LIE on your applications. But also do not give them any more information than what they ask for.
Good Luck, and stay strong. My husband is now a permanent resident, applied for citizenship and working his way into the corporate business world now. Things will get better!