The official Washington state tourist website is ExperienceWashington.com.  However, there are many other sites which focus on tourism in particular parts of Washington, or on different interests.  If you are planning on visiting Seattle, visit Seattle's Convention and Visitors Bureau.  If you are planning a visit to Spokane, visit Spokane's Convention and Visitors Bureau. Does a trip to the San Juan Islands strike your fancy?  Then take a look at the Guide to the San Juans.  If you plan on visiting the Olympic Peninsula, you may find the Olympic Peninsula website helpful. 

If you're visiting Washington in the Spring or Summer, you will probably want to visit one of the many festivals.  The Tulip Festival in the Skagit Valley occurs in March and April, and the Lavender Festival in Sequim takes place in July.  The Apple Blossom Festival occurs in late April/early May, and you won't want to miss OysterFest in October.

This is the Official Washington State Government Visiting and Recreation webpage. Here is the link to some Washington State Facts.

City of Olympia, Washington State ( Capital City of the Evergreen State )

Washington State Travel Counselor at 1-800-544-1800.
They're available Monday through Friday from 8:00 a.m. to 5:00 p.m. (PST)
(Closed on all major U.S. holidays) 
E-mail at: tourism@cted.wa.gov

Seattle's Convention and Visitors Bureau
One Convention Place                                                                                                                                                                                                            701 Pike Street, Suite 800
Seattle, WA 98101
Tel:  206.461.5840 (TDD accessible)
Fax:  206.461.5855
Email: visinfo@visitseattle.org

Spokane's Convention and Visitors Bureau
801 W. Riverside, Ste. 301                                                                                                                                                                                         Spokane, WA 99201
Tel:  509.624.1341                                                                                                                                                                                                                   Fax:  509.623.1297
Toll: 800-662-0084                                                                                                                                                                                 http://www.visitspokane.com/index.php