There are several sources for agents, but getting a good one is always the key issue. Find a Pro, here in Trulia can show you some local agents who are active here on Trulia. You can read some of their responses to question and their blog posts to get a sense of who they are and how they think.
Referrals from friends are another source to find a good agent.
When you've found 3 or 4 that are worth considering, interview them and ask what they bring to the table. Each should have their own story about their skills, experience and market knowledge. Being "qualified" only means having a license, being truly qualified and a quality agent means having extensive knowledge of your local market area, recent success selling similar homes, an extensive marketing plan for your home, the ability to assist you with preparing your home for the market and finally skill in negotiating to obtain the best possible terms for your sale. Price is not the only factor when negotiating on the sale of your home. There are so many factors to consider and evaluate an offer I may have to write a blog post about it. I hope this was helpful.