Most professional massage schools throughout the nation are going to require at least age 18 or 19, high school diploma or equivalent. Accredited schools may have financial aid available. Plan on 9-12 months of school, exam prep and completion of license. Washington state is a great place for massage therapy due to its acceptance with insurance companies. Cost of education & training will probably be upwards of $10g. The first step should be contacting the Washington State Board of Massage Therapy, where they will have the statutes, rules and regulations and the staff to help explain to you what is common practice toward licensure. They will probably not recommend a specific school since it could be favoritism by the state. But, they will have all the approved schools and any disciplinary actions on the schools. It could help narrow your search so you can contact 2-3 to start asking more questions. If you are planning to practice in a different state other than Washington, then it is imperative that you check with that state's requirements prior to going to school. Each state is going to be different. Best wishes...
Washington State Board of Massage
http://www.doh.wa.gov/hsqa/Professions/Massage_Therapy/default.htm