Hi George,

Use the bibliography (and the contents) of "A Scoping Review of Health Game Research: Past, Present and Future" to see a good compilation of literature in the area:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3884078/

You also have specialized journals such as:

http://www.liebertpub.com/overview/games-for-health-journal/588/