You sound like a pretty confident outgoing guy. I expect you will have no problems meeting new people in Austin.
It is totally fine going out alone and meeting people. I personally spend a lot of time in public places alone. I bring a book to read, and when I see a cute girl I approach her. I've gotten 3 female and 2 male friends out of this experience. I actually went to a local battle of the bands a few weeks ago, by myself. I was one of the few people to wear a blanket, because it was super cold. And I felt really odd for doing so. But since it was sooo cold it worked out really well. I actually ended up meeting a cute girl, and I took her on a date a few days later. So don't be afraid to be a little different.
The best way to meet people alone is to approach them positively:
Hey I found the party! How are ya'll doing?
You guys look like you are having so much fun, that I have to join you.
You can also try one of Nick's social exercises. Go to a public place and join a group of people. After a few minutes go join another group for a bit. Keep group hopping for a bit. When you return to the first group, they might try to encourage you not to leave. They might fight for your attention.
Your #2 is probably the best way to meet women. That feels more natural and women have other people that can verify that you aren't a creep. Plus you are becoming a more interesting person when you invest in yourself.