I always had a problem with making friends and the best friends I have had so far have mostly been online. In fact, my two friends that I hang out with in person, were both met online and we became online friends first, despite living in the same city. I have also met 2 other people from abroad, that I had been friends with online for over a year before that.

I think that meeting people online can sometimes even be more genuine because a lot of shy, introverted people can actually be a bit more open and show more of their true selves online, with less pressure put on them and then there's also the fact that, usually, social status and looks don't matter and the first impression is made in the best way, through what the person says and thinks, their behavior.
What is also an advantage is that you can meet these people on sites/forums for those interested in the things you are interested in so you share hobbies and/or views from the get go.