The same way you start a conversation with anyone else, they are no different to other people! Just find a common point go with it

If you know they are American you can ask what state they are from. There are 50 and all are different. (in case you didn't know)

Tell them that you've seen their profile, and that you are interested. Then say that you have a lot of money in an African bank account that is only available to you with the help of your new friend. If it is possible, you would like some help in facilitating that transaction. Ask him to contact you via MSN, and then add that race and distance don't matter in a love relationship.

Well, after you say hello and introduce yourself, make sure you mention where you found out about them. For example, people find me on Skype or AIM and unless they state they are from iTalki or another website I go on, I am hesitant to talk to them. After you have started the conversation, keep talking. One thing that really bothers me is when people will message me, say hello, how are you, and then stop talking. I understand there may be language difficulties but it's better to try.