A simple way to find out if the offer is genuine is by being patient and watching their moves carefully. If they ask you send them cash through Western Union or any other money transferring agency usually in the name of some person, you can be almost sure it is a fraud. They usually state the money is required for legalization of documents, or documents/visa processing fee etc. Another way is by checking the address on their letter head when you receive the offer. You can check from their zip code (if they have one on the letter head) through Google if that company exists at the location they are stating. I receive such offers sometimes also, but I use the above two simple methods to get to know the reality. Surely, there may be other ways, and hopefully some of the gentlemen who contribute to QL could throw more light on this matter.