New Earth: Wagon Train to the Stars — Diane Carey

After saving Earth from the threat of V'Ger, James T. Kirk is called again to the final frontier. His new mission: to lead a valiant group of settlers to a distant world, to defend the struggling colony from alien threats, and to explore the diverse mysteries and dangers of a strange new Earth!

Far from the Federation, a newly discovered M-class world has been eyed as a potential home by a group of hardy and determined colonists. Starþeet can spare only one starship to escort the would-be settlers on their perilous voyage, but that ship is none other than the legendary Starship Enterprise™, commanded by the most well-known captain in the quadrant. Now Kirk finds himself responsible for the lives of 30,000 men, women, and children -- a task that grows all the more difficult when the expedition is caught in the middle of an ancient feud between two dangerous alien races!