Tobacco Control
Most archival content available to view free of charge
http://tobaccocontrol.bmj.com/info/about.dtl
The Medical Journal of Australia
Most content available to view free of charge
http://www.mja.com.au/
The British Medical Journal
Most archival and a sizeable proportion of current content available to view free of charge
http://www.bmj.com/
The Cochrane Collaboration - Cochrane reviews
Searchable database of international, authoritative reviews on a range of health issues including tobacco use
http://www.cochrane.org/reviews/
American Journal of Public Health
Most archival content available to view free of charge
http://www.ajph.org/