A lot of comedians promote themselves by sending MySpace bulletins every time they have an upcoming show. Usually, they post the bulletin only a couple of hours before the show is scheduled to start.
This strategy falls short, and not just because the promotion should have started days beforehand. Out of everyone in your friends list, only a few of them will read your posting. If you're lucky, you may get a small percentage of the people reading your posting to actually attend your show. Do you see a problem here?
My advice to you is to promote your shows and content outside of your regular network. If you're a comedian, consider going to a Toastmasters meeting. You'll be able to promote your shows to people who most likely don't know about the local comedy scene. Another added benefit is if you join Toastmasters, you can help your public speaking skills, which will definitely translate into better comedy performances.
Get your own domain name and start a blog there. If you have a blog, you can register it through blogging social networks and blog registries. If you have entertaining or useful content that is updated regularly, you will attract readers. On one of your pages of your website, list all of the comedy shows that you will be doing. This way, your audience will find you through the search engines.
If you like to write, there are some websites that will actually pay you for your submissions. Associated Content, Ehow.com, Helium, and Hubpages are just a few of them. I am on all four of these websites, and I can assure you they are legitimate. You can find talented writers on these websites that you may not easily find on MySpace or Facebook, and add them on your network there.
Following these tips will help you get a following.