Before you get out there and start meeting with possible candidates, you need to make a list of possible photographers whose work is appealing to you. One way for you to begin is to talk to your friends who have recently gotten married about their experience with their photographer and to flip through their wedding albums to see if you have similar expectations for the final outcome of the pictures.
Another way to begin finding possible candidates is to talk to other people who are helping you plan different aspects of your wedding. Your caterer or wedding coordinator may know an amazing photographer and give you a recommendation or they may just be able to give you a list of possibilities that they have previously worked with. If these methods have not worked, you can attend a bridal show and meet the photographers in person to discuss their style while also viewing their previous wedding work.