Twitter recently updated their search feature, you can view it at http://search.twitter.com. It works pretty well, just type in your search terms and you will be given the latest tweets that match your terms.
I found today that it can be a great tool to find freelance jobs, you can use a similar query to find what you are looking for; http://search.twitter.com/search?q=freelance+web. You could probably spend an hour tweaking your search to find 20+ people to follow, some are automated feeds that just display jobs/gigs and some are people posting jobs. Either way, it can be a nice automated way to find freelance work, after you set it up.
Here are a few twitter profiles that you can follow to help get you started: