Most realtors will do work as a Buyer's agent. There's not a special different license or specialty you look for; just that their principal is YOU and not the Seller.
The work is similar, when you buy, typically you sign allow the sellers agent to be a double agent but with the knowledge that this is to reduce cost reduction.
When you get started, you should have a signed contract indicating Buyer's Agent-if this is indeed what you are looking for and willing to pay extra for. Contracts should also be standard contract forms, not something they whipped up. Review and talk over what their commission gets you and what services you want. Negotiate and understand what you want in a Buyer's agent.
Talk over if you expect them to find and handhold you through houses they pick, or if you can go look and visit houses by yourself on the internet, and all you need is crash course on that and final representation when you identify something you like and comes time to make an offer and closing a deal.
I would say the main thing to is go with a Realtor that highly knows the area and has been around for awhile. They should be fairly tech savvy as listings are all online. So their office should have modern looking computers with people actively doing most of the work on computers. If they are browsing listings in magazines and newspapers, move on.