Ex-gladiator returning after 7 years. In need of some serious help.

I recently started playing WoW again and I'm really just looking for some pointers on how to get back into rated PvP. I main a priest and alt hunter. PvE is not my thing in the slightest. Currently leaving to 120 and just wondering, is there a decent guide on how to get geared now? Like what I should be doing once I hit 120. I am extremely out of the loop. To put things in perspective I have gotten married and fathered 3 children since leaving the game. Haha. Not sure what the best resources are these days. Primarily looking for serious help. I know the game isn't in the best state and I'm sure people are wondering why I returned but thats not really what I'm looking to discuss. Thanks in advance.