Your initial information about a broker will come from his web page or some advertising material that you have seen. Go online and visit forums and places where reviews are available. Correspond with people who have used these brokers and get an idea about their customer support, spreads, and ways that they execute trades. Look for news regarding these brokers and if you find any that is derogatory, start looking for other brokers. After all you do not want to risk your money with someone who does not have a good reputation.