lahnnabell is right on with her comment:
I think you should practice socializing my making more friends first. Learn how to talk to people, guys and girls. Take inventory of your interests and start developing some hobbies around them. Do you like reading? Join some sort of book club. They have them for comics, graphic novels, romance, science fiction... Whatever. Gaming, baseball, surfing, anything.
Dating is a social activity. So if you're not very social as it is, you gotta start with the basics.
Stop even worrying about dating right now. Just go do things. Get involved with groups, hobbies, outings, events. You will wind up meeting people through these things (both men and women) who share a common interest as you. That could, and will, be the seed for conversations, getting to know one another, etc. It will also allow you to open up more, as you say, to the possibility of going out with someone.
In effect, online dating is the same concept. Everyone on the online dating site already has a common interest - getting a date.
If you think your social skills are that unhealthy, I would suggest seeing a counselor of some kind. You need to figure out a way to work past these issues of self-doubt you have. Confidence is the most important factor in being in any sort of relationship.
Concentrate on you first and the rest will follow.
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