Taken from archive.org

from 2019-now, the budget is at
  https://www.seattleschools.org/departments/finance/budget/

from 2016-2018, the budget was at
 http://seattleschools.org/cms/One.aspx?portalId=627&pageId=4236325

for 2015, the budget was at
  http://sps.ss8.sharpschool.com/cms/one.aspx?portalId=627&pageId=14984

for 2007-2014 the budget is all findable at
  http://seattleschools.org/modules/cms/pages.phtml?sessionid=&pageid=225568

for 2004-2005, the budget is at

  There is no purple book. The have a "blue book" instead with one PDF per
  school:
    https://web.archive.org/web/20051003213015/http://www.seattleschools.org/area/finance/navsubs.nav?index=5

for 2002-2003 the budget is at
  http://www.seattleschools.org/area/finance/budget/index.html