Gopher has some of the best tutorials on getting started with modding and makes a few extremely useful & popular mods.
Playlist URL:
https://www.youtube.com/playlist?list=PLE7DlYarj-DdhDG41roBVJfNCqvO5MmKP
Here are some of his other useful playlists:
Skyrim Tweaks and Fixes
Skyrim ENB Mods
Mod Organizer Introduction
Other Useful Sites:
GAMEFAQS: Skyrim Console Class 101
Youtubers:
Antony Bellingham - Creation Kit Tutorials
LouisAT444 - Creation Kit Tutorials
