What do I need to know?

[smidge146]

I'm trying to make an addon which spawns NPC at random coordinates in the map and when the player looks at them, they disappear.

What things do I need to learn to do this?
Also, Do you know of any gmod lua websites?

[NullPoint]

[b][url=wiki.garrysmod.com/?title=Math.random]Math.random [img]http://wiki.garrysmod.com/favicon.ico[/img][/url][/b]
[b][url=wiki.garrysmod.com/?title=Ents.Create]Ents.Create [img]http://wiki.garrysmod.com/favicon.ico[/img][/url][/b]
[b][url=wiki.garrysmod.com/?title=Entity.SetPos]Entity.SetPos [img]http://wiki.garrysmod.com/favicon.ico[/img][/url][/b]
[b][url=wiki.garrysmod.com/?title=Player.GetEyeTrace]Player.GetEyeTrace [img]http://wiki.garrysmod.com/favicon.ico[/img][/url][/b]

[editline]05:50PM[/editline]

[b][url=wiki.garrysmod.com/?title=Timer.Create]Timer.Create [img]http://wiki.garrysmod.com/favicon.ico[/img][/url][/b]