How do you know that this girl is single? If your source is reliable then the person must
know someone who knows someone who knows her. If that is the case then get them to relay your interest in her.
You don't really need to know any of her friends. You only need to know someone who knows one of them and presto you have a chance at an introduction.
Sending a message as a secret admirer can be a double edged sword. You are better of being upfront on who you are and that you like her. She will appreciate the honesty and could
very well be flattered enough to say yes.
If you do send her a message with your name on it (& picture if you want) then why not put
in some of your friends names and mobile numbers as references? You can say "hi my name is <your name> I really find your good looking, would you like to go out for some coffee
sometime? We have never really spoken before so if you have any concerns then please call
any of my friends. They should hopefully vouch for my sanity
(note: make sure that you
ask your friends first and if you can include a girl or two then that would be good.
Good luck with it - Bud.