PvP is not everybody's favorite thing. I tend to avoid it for the most part although I know how it works in case it comes up. That being said, there's a quest you can get at 51st level (which is the earliest you can go to Alterac Valley) that the reward for is really worthwhile. Depending on what class you are, it's usually a blue rarity weapon that does considerably more damage than anything else you'll find at that level. For example, a warrior can select the Ice Barbed Spear, a polearm that does an immense amount of damage. My mage recently got her Wand of Bitter Frost which is both fast, damaging, and adds to the damage of any frost spells I cast.
So, the quest is simplicity itself. You only have to go and participate in an Alterac Valley battle, and be on the winning side. You only have to do this once, and then claim your reward. The return on your investment of time is incredible. Additionally, as PvP battlegrounds go, Alterac Valley is a little complicated, but it's really exciting. A full scale battle between the Aliance forces and the Frost Wolf foe with strategic objectives, and NPC defenders. It's pretty cool.
Feel free to check it out, and if you have any questions, let me know. I'll try to answer them to the best of my ability.