Welcome to the fold Steve.
I myself use wowprogramming.com, WoWWiki, WoWInterface, Curseforge and of corse google.
Yes there are limitations of what you can do in the game. For example events can not make the player automatically cast spells etc. These can only be done by actions initiated by the player (keyboard or mouseclick).
If you are simply interested in finding someting that is already created then you should look at my addon called IfThen:
http://www.wowinterface.com/download...11-IfThen.html
It has a IDE and fully documented API to write simple IF-statements to react to events ingame, just like you mentioned in your example.
A quick example of the addon's syntax.
Code:
OnEvent("Buff") AND HasBuff("Heroism") OR HasBuff("Time Warp") THEN Print("!!!==Heroism || Time Warp==!!!");