See the sticky at the top?
read it, it has everything you need to become a good raiding hunter and more.
As for PvP, get honoured reputation with Honor's Hold/Thrallmar (revered for the PvE weapon is better), Lower City, Keepers of Time, aldor/scryer and Sha'tar and revered with Cenarion Expedition.
This to get you all the reputation PvP pieces, a shoulderenchant and the Glyph from Cenarion Expedition.
Except for sha'tar all are doable while leveling and not too hard, sha'tar you can get quite close through rep gained with aldor/scryers.
If you havent chosen yet, aldor is the better choice for both the shoulderenchant and the SSO necklace.
After you get that, and combined with the gear you got from getting honoured with those factions you'll have a decent starter PvP set.
I also recommend getting the
disco axe from AH for a couple gold to give you a decent PvP weapon.
Complete your set with some pieces that give stamina and hit to get you to ~79 +hit (gem for hit and agi/hit to help) and you'll have enough survivability to do BG's without being cannonfodder.