Sometimes finding information on your car is the hardest battle.
Here is a list of OEM (Original Engineering Manufacturer) tech sites

• 
  Acura: http://www.serviceexpress.honda.com
  Audi: http://erwin.audi.de
  BMW: http://www.bmwtechinfo.com (or http://www.bmwtis.com)
  Diamler Chrysler: http://www.techauthority.com
  Ford: http://www.motorcraftservice.com
  GM: http://www.acdelco.com or http://www.gmtechinfo.com or http://www.gmgoodwrench.com/gmgoodwrenchjsp/gmspo/index.jsp
  Honda/Acura: http://www.ServiceExpress.Honda.com
  Hyundai: http://www.hmaservice.com
  Infiniti: http://www.infinititechinfo.com
  Isuzu: http://www.IsuzuSource.com or http://www.IsuzuTechInfo.com
  Jaguar: http://www.jaguartechinfo.com
  Kia: http://www.kiatechinfo.com
  Land Rover: http://www.landrovertechinfo.com
  Lexus: http://techinfo.lexus.com
  Mazda: http://www.mazdatechinfo.com
  Mercedes-Benz: http://www.startekinfo.com
  Mini: http://www.minitechinfo.com
  Mitsubishi: http://www.mitsubishitechinfo.com
  Nissan: http://www.nissan-techinfo.com
  Porsche: http://techinfo.porsche.com
  Saab: http://www.saabtechinfo.com
  Saturn: http://www.gmtechinfo.com
  Subaru: http://techinfo.subaru.com
  Suzuki: http://www.suzukitechinfo.com
  Toyota: http://techinfo.toyota.com
  Volkswagen: http://www.erwin.volkswagen.com
  Volvo: http://www.volvotechinfo.com
  
  

Other Tech information:

• Old Car Manual Project Old Manuals, Brochures, Ads, and Pictures of Chevy, Ford, Buick, Oldsmobile, Pontiac, and Chrysler cars.
• Old Chevy Manuals Old Chevy Manuals, Free to view!