There is a really nice guide on the maven site about how to encrypt passwords that get stored within POM files located at http://maven.apache.org/guides/mini/guide-encryption.html
Can these operations be done within eclipse using the m2e plugin, or must I have my guys download maven before they can create encrypted passwords and master passwords?
m2e comes with an embedded maven installation. From Eclipse (using Run configurations) you can run arbitrary maven commands, including the ones related to password encryption.
Also see this related SO question