If you're unsure of what to say in your introduction we're always interested in learning whatever we can.
How about answering some of these questions in your post?
What do you like to be called?
Where are you from/located?
What's the weather like where you are?
What do you do for fun?
Did you perv the site before you decided to join?
What made you join
What are you looking forward to on
What are you hoping to gain from
Please understand that these are just suggestions and you're welcome to post whatever you want. Just be sure to post more then "I don't know what to say but here I am!". I've given you a good bit to start off with.