There are a host of great free resources on the web for those going as missionaries long-term, short term, and for those helping to send missions workers. These resources are useful even for English teachers carrying the Life of the Gospel abroad! Here’s a list compiled by Seth Barnes at Adventures In Missions:
Missionary Care The most thorough list of articles and ebooks I’ve seen
Ask a Missionary Great web site with answers to your questions from experienced missionaries
Ethne-Member Care A list of articles
Going Global: A Member Care Model for Best Practice
Stephanas: A New Testament Example of member care
Supporting Mission Workers The Key Role of the Sending Church
Sending Church Profile, Raising the Standard, Focus on Member Care Articles by Neal Pirolo
Historical Perspectives
For Everything There is a Season…And a Summons
To the Ends of the Earth
Wise as Doves and Innocent as Serpents In 12 languages
Giants Foxes Wolves, and Flies In 5 languages
Great Commission Resources Joshua Project
IJFM, Issue on Member Care
Doing Member Care Well Best book on how to send and care for missionaries
WEA Resources A list of articles and books available in Spanish and Arabic
Missionary Care: Counting the Cost 25 chapters available to download
People In Aid Note their list of publications in Resources & Publications
And… here’s a link to Seth Barnes’ Blog, Radical Living in a Comfortable World
J. Scott Husted -- Through the Veil 