temporary tutorial page:

look at these places for good tutorials

S&box:

Official S&box Discord: https://discord.com/invite/sbox

Official Docs: https://docs.facepunch.com/s/sbox-dev/

Official Wiki: https://wiki.facepunch.com/sbox/

Official API Reference: https://sbox.game/api

Youtube channels with tutorials:

Carson Kompon (Code): https://www.youtube.com/@CarsonKompon

Small Fish (Code): https://www.youtube.com/@SmallFishDev

Me (Maps): https://www.youtube.com/@Gvarados

Eagle One (Maps): https://www.youtube.com/@eagleonedevelopmentteam849

Source 2:

My Video Tutorials: https://www.youtube.com/playlist?list=PLrUY-5TMELbdLXXVaIvIbP7qogJVPAypr

Tutorials by Hosomi: https://www.youtube.com/user/SurendaOtoko/videos

Eagle One Tutorial Series: https://www.youtube.com/channel/UC0AxhGwR8Zjbq1gPXGwmTog/videos

Shy Studios video: https://www.youtube.com/watch?v=nfIW_2sDphc

Shy Studios video part 2: https://www.youtube.com/watch?v=VR_K0oz9Jok

My Tips & tricks thread on facepunch forums: https://forum.facepunch.com/t/mapping-resources-tips-tricks/1030

Source 2 Hammer introduction by Marnamai: https://docs.google.com/document/d/17aFk2Z-C1G2ZYcQRxKx-fEK3m4h0jSw9nqGjC9T1Bx4/

Valve Wiki HLA: https://developer.valvesoftware.com/wiki/Half-Life:_Alyx_Workshop_Tools

Valve Wiki SteamVR: https://developer.valvesoftware.com/wiki/SteamVR/Environments

Valve Wiki Dota 2: https://developer.valvesoftware.com/wiki/Dota_2_Workshop_Tools

Look at all the valve wikis. There are different tutorials on each wiki but they all work on any game.

Note: HLA and s&box use a newer model editor

Note 2: Most Source 1 tutorials mapping will also work on Source 2. (but probably not s&box)

S&box Modding Discord: https://discord.gg/K4Jv7G3WUw

Source 1:

UEAKCrash: https://www.youtube.com/watch?v=isYxpHz4GWQ&list=PL2KT0JL74QfcI2FSN_MdQ7agYL4DmP7hZ

TopHATTwaffle: https://www.tophattwaffle.com/tutorials/

3kliksphilip: https://web.archive.org/web/20160616203026/http://3kliksphilip.com/tutorials/sdk_specific.html

My Tips & tricks thread on gmodstore forums: https://www.gmodstore.com/community/threads/6995

Tips & tricks on knockout forums: https://knockout.chat/thread/862

Valve Wiki: https://developer.valvesoftware.com/wiki/SDK_Docs

Garry’s Mod beginner’s guide:
I recommend following UEAKCrash’s video series, starting on episode 2. (Ep1 is specific to TF2.)
https://www.youtube.com/watch?v=VfK1WSo0xj0&list=PL2KT0JL74QfcI2FSN_MdQ7agYL4DmP7hZ&index=11
Hammer is located in Steam\steamapps\common\GarrysMod\bin
I recommend making a shortcut on your desktop.

Both:

My Youtube: https://www.youtube.com/c/Gvarados/videos

Shy Studios website: http://shystudios.us/