I fully believe that a buyer and his/her interests are, in almost all cases, best served by having an experienced and knowledgeable buyer's agent.
However, my recommendation for the first course of action is for a propsective buyer to utilize some of the many resources available to the public to become more familiar with their local marketplace. Spend some time searching properties on Trulia and Realtor.com. Go to a few open houses.
If the buyer already have a buyer's agent, or has had one recommended, great. If not, through preliminary research, I suggest a propsective buyer watch and listen to the advice and information provided by the Realtors with whom they interact. Choose a buyer's agent based on skill, knowledge, capabilities and compatibility. Don't choose a buyer's agent soley on happenstance because you cross paths with him or her.
Many broker and agent sites will provide an option to sign up for automatic email updates of homes that meet specified search criteria.
There are many resources available. Knowledge empowers buyers and allows them to feel more confident in their decisions.
As a buyer progresses on the path in his/her search, a more solid relationship develops with a realtor that has become familiar with the buyers wants.
The first course of action is to become familiar with the basics of the market, meet a few agents, and find the right one.