The Scottish Tourist Board is known as VisitScotland. You can request regional brochures to be posted out to you, or download them from the website.
Most larger towns have tourist offices ('information centres') that open from 9am or 10am to 5pm Monday to Friday, and at weekends in summer. In small places, particularly in the Highlands, tourist offices only open from Easter to September.
If you want to email a tourist office, it's [inserttownname]@visitscotland.com.