I am not too sure how I feel about this character yet. I guess it would be okay if Galbatorix had a few bad guys that supported him but I also feel there should be a lot of people force by oaths to support him.
As for the book according to the IC wiki:
During Eragon's travel to the Varden from Eastcroft, Eragon and Arya came across a patrol of Galbatorix's soldiers. This soldier halted his company and began questioning Eragon about what they were doing in those parts. He ordered one of his men, Langward, to search their belongings, when he found Eragon's armor. This soldier then ordered for them to be tied up, but Eragon had other plans. He used magic and lifted a pebble up, thrusting it at the soldier and puncturing the side of his helmet.
He had an enormous curly mustache descending to the corners of his mouth, extending nine inches in either direction and was in stark contrast to his straight hair that fell to his shoulders. He wore gloves and the traditional Imperial uniform and rode a roan charger.