For a free travel packet that includes the very helpful Washington State Visitors Guide, contact Washington State Tourism (800/544-1800, www.experiencewashington.com [1]). Its website provides comprehensive details and links on Washington travel. You can also pick up maps and brochures in person at the larger visitors centers around Washington.
For details on Washington’s federal lands, visit the Outdoor Recreation Information Center inside the Seattle REI store (222 Yale Ave. N, 206/470-4060). It is staffed by National Park Service and Forest Service personnel who can answer your questions on hiking trails, campgrounds, and backcountry access. Ranger stations at the national parks and forests can sell you forest and topographic maps and provide campground and trail information and other printed material.
Links:
[1] http://www.experiencewashington.com