This is the home for the Shadowlands campaign setting, run by Garrett A. Forrest.
Here are some resources that are available on the internet. They are essentially all compilations of 5e Dungeons and Dragons OGC from Wizards of the Coast.
Roll20: This is an incredible resource to look up rules, classes, items, etc.
Orcpub: This website has a concise list of monsters and NPCs with their experience values clearly visible.
D&D Wiki: D&D wiki is an excellent resource for homebrew content, and it has the best, and most complete, spell list of any website.
5eSRD: This and Pathfinder SRD are the most comprehensive collections of information available for the game, and they also serve as an excellent third party publisher database.