A few thoughts on this:
Chamber of Commerce - Often local chambers have various types of speakers present on topics of community interest. I'm a radiologist and gave a talk on 3D mammography to a local chamber and saw our screening rates dramatically increase.
Loca Paper Guest Columnist - Local papers are hungry for content. If you are an expert and can write about health issues such as but not limited to preventative services you will likely have your work published.
Community Services Groups - Similar to Chamber's of Commerce, local Rotary, Lions, and City Clubs are often receptive to various speakers including health professionals.
Community Health Events - Does you county or city public health department put on an annual health fair? Can you participate, perhaps have a both and offer a free service there?