Online dating is a game of fishing. You need to build your social skillset before you can catch anything worth-while.
I have some advice if you are looking to gain worthwhile experience.
1) Never ask a chick out online (or in text, or whichever other impersonal method you have concocted in your mind).
2) Avoid the desperation vibe. You, good sir, must put forward your character and personality in order to win a woman's trust and more-than-passing interest. If all you are bringing to the table is that you want a relationship you aren't going to sell yourself very well.
3) Take it slow. Generally, you want to wait until she makes the first move to ask to see you in person. Like in fishing, if you pull the line too soon, you are bound to scare away the fish! The moment you aren't looking for someone, you are bound to meet a worthwhile person.
4) There are plenty of fish in the sea. You lost that one, move on. Have some fun just being yourself. Don't expect anything out of a dating site (once you have that attitude, you'll enjoy your experience much more).