Ok basically its very simple here's what I did. I made a new character hunter/ dwarf. My girlfriend has a level 30 Rogue and my friend has a level 55 pally. They spent a few hours following my newbie character around Killing all the stuff I flagged (Basically My little guy attacked the creature hit it 1 or 2 times then they killed it off for me) You can tell when you have flagged a creature because the nameplate turnes red for you and turns grey for other attacking people which means they will not receive loot/exp for the kill.

You must note, we were not grouped. I flagged the NPC's and they killed it in 1 or 2 swift hits and I got all the exp! I believe I got to level 10 in around 45 min fighting the frostmane trolls and those small yeti's near kharanos (city just outside IronForge) (Also completed some simple quests which gave me exp as well).

Once I got to 10 I headed to Loch Modan area and into the stonesplinter valley. It's infested WITH TONS OF TROGGS that never run out and I went from 10-17 I believe in less then another hour! It was awesome exp, and I barely had to do any work.

Once I hit 17 we went to the Ogre Mound in Loch modan and did the same thing. However, I used my pet to flag the enemy instead And I went from 17-23 in around 45 min.

Now I didnt exactly time all this so the times might be a little off I estimated on them basically but this worked great for me and I went to lvl 23 in less than 8 hours grinding (Extra time was added in for training, Repairing, Shopping, Traveling, Resting etc...). Thats As far as I got Im sure there are better places to use this technique for more exp etc.. I am gonna try this again with a Mage character and try to do it in less time and make it more effcient. Ill repost on my findings, hope this helps.