May the Grind Be With You - Terokkar's Shadow Tomb

The best grinding spots are places where the mobs are relatively easy for their level, plentiful, but not dangerously so, and somewhere where you'll be safe and left in peace by both factions.

Go to Terokkar and look on your map. In the Bone Wastes, there are 2 icons for buildings of a sort. The one on the left is a Shadow Tomb. It's a 3-wing area, and each wing has 7 to 10 mobs, built of warrior types, mage types, and rogue types. Now, the rogues don't stealth, the mages don't do much damage, and the warriors are rather squishy. They're level 64 and 65, mostly.

This spot is a fantastic place to grind from maybe 65 or 66 on. Not only will you get tons of Aldor rep items (Marks of Kil'Jaeden and Fel Armaments), you'll rarely find other players in here, because most people grind on the mobs above the surface, not in the tomb. The mobs are easy to pull one at a time, and even if you pull two, you can probably handle it. I grinded here for about 1 hour, and I got 3 greens, 1 blue (Boots of Savagery), 50 marks of Kil'Jaeden, 4 stacks of Netherweave, and 1 stack of Runecloth. I was averaging about 120,000xp per hour, because by the time you clear the last wing, the 1st wing is respawned. There is almost no downtime aside from resting.

Grind on!