U.S.
Consumer Price Index (US Bureau of Labor Statistics)
Historical CPI - All Urban Consumers (Municipal Research & Services Center)
Historical CPI - Urban Wage and Clerical Workers (Municipal Research & Services Center)
Per Capita Income (US Bureau of Economic Analysis)
FedStats - gateway to statistics from over 100 U.S. Federal agencies
HUD User Policy Development and Research Information Service

Washington State
Labor Force Statistics (WA State Employment Security Dept)
Annual Population Estimates by Jurisdiction (WA State Office of Financial Management)
Washington State Office of Financial Management (OFM) Forecasting Division — Population estimates for cities, towns and counties, Housing unit estimates for cities, towns and counties, County Growth Management Act (GMA) population projections, State Population Forecasts, Annexation Data
Washington Center for Real Estate Research

Local
King County Budget Office — Comprehensive Plan, Buildable Lands Report, Buildable Lands Report, Annual Growth Report, Benchmark Report
Kitsap County Department of Community Development — Comprehensive Plan, Buildable Lands Report
Pierce County Planning and Land Services Department — Comprehensive Plan, Buildable Lands Report
Snohomish County Department of Planning and Development Services - Comprehensive Plan, Buildable Lands Report, Growth Monitoring Report
King County Annual Growth Report
NWMLS
UrbanSim

Census
U.S. Census Bureau
Census 2000 Data for the State of Washington
Washington State Office of Financial Management
King County Budget Office
Seattle Times articles
Seattle P-I articles
Tacoma News Tribune articles