When you first enter Spineridge from the west the first building to the north is the inn. Inside the common room you will find Vairlas standing near one of the tables. Vairlas identifies items for a very steep price. I don't recommend using him. Standing behind the bar is McClain, the innkeeper.
East of the inn is Alzron's office. Alzron provides several functions. He serves as a Job Dispatcher, and he sells a few items. Alzron is like Levy in Fort Emergence, in that any item you sell him he will then have an unlimited supply of. Alzron also gives you a quest to bring him writing supplies. You get 20 coins for each item, and a small amount of experience.
South of Azron is the town fletcher, who sells Blessed Missiles instead of Iron or Steel.