First find a carrier. Then think about what you want from a phone. Great camera? fast phone? large amount of space? high resolution screen? large phone or small phone? heavy or light? and so on then visit the two websites and compare and find a phone read reviews. http://www.phonescoop.com/ http://www.phonearena.com/
What is your budget?
What do you need from your new phone?
What do you want from your phone?
What are your expectations from your new phone?
Which features can you not live without?