The Community Health Maps blog has some great tutorials by Kurt Menke.

Great free QGIS tutorials by Ujaval Gandhi.

Free tutorials on the semi-automatic classification plugin that turns QGIS into remote sensing software.

Introduction to QGIS Python programming for non-programmers. By Anita Graser.

Many free tutorials on open source for groundwater modelling.

This workshop will discuss approaches and guidelines for creating map figures for academic books and journals. By Michele Tobias.

Un libro libre de Víctor Olaya.

The MapScaping Podcast is a weekly podcast featuring interesting people doing amazing work in the geospatial world. 

The Geomob podcast discusse themes from the geo industry, interview Geomob speakers, and provide regular updates about projects. They publish a new episode every week.