Need help with finding raids and things like that.

Hello,
I need help with finding groups for raids ICC rep farm and things like that. Iam very very new to this things and mostly i dont understand what are other people saying when they looking for someone to fill their party.. I mean i understand when someone say ICC but thats all..
Can someone explain me those shortcuts? TOC, HOS, FOS, EOS, EOT or FROST and there is much more things that i doesnt understand.. Sure someone would say "Just find it on google man." and that leads to my another question. As a player who never played raids and who only played RDF HC iam kinda lost..
Iam currently playing as retri paladin with 4,8k GS properly enchanted but not gemmed yet and i dont know what raids or dungeon should i prefer for acquiring items with better GS.
And if you help me with that, i need also know for what items should i look from each specific raid or dungeon.

I hope thats all for now and i will ask later for more things like emblem vendors and their items ^^
Thanks to all who will help me with that.. I really appreciate it.

here is a bunch of stuff that will help you https://forum.warmane.com/showthread...=1#post2676312