Each of these has many resources available to non-members (and even more for members):
Biomedical and Life Sciences Division — part of the Special Libraries Association (SLA)
CAPHIS — Consumer and Patient Health Information Section — part of the Medical Library Association (MLA)
Medical Informatics Special Interest Group — part of the American Society for Information Science and Technology (ASIS&T)
Medical Library Association (MLA)
National Network of Libraries of Medicine (NN/LM)
Pharmaceutical and Health Technology Division — part of the Special Libraries Association (SLA)