Libraries.io indexes data from 2,354,146 projects from 33 package managers. We monitor project releases, analyse each project's code, community, distribution and documentation, and we map the relationships between projects when they're declared as a dependency. The 'dependency tree' that emerges is the core of the services that we provide.
https://www.udemy.com -> Most of the time they got specials for like R100/R200 on a course for whichever programming language you want to learn. Some of the courses has quite a big community behind it, where you ask anything ,you can even ask the instructor himself.