Level 8 now. At this point, I only gain experience from level 3 and above.
There's plenty of level 3 creatures to go hunt, but @ 16 XP a pop (and I need 6140 to get to 9) it's just not worth the effort.
Level 4 creatures? Just not enough of them and when you do find a small cluster, it takes a while to get to them.
Level 5. There's two Melandru's Stalkers out in Regent Valley, but the time walking back and forth from the warp zone would kill you. There are 4 level 5 charr that you can go after in the Charr at the Gates quest (you can abandon the quest and keep re-doing it), but unless you do most of the damage you won't get the experience (so you leave Rurik behind and do it solo). This would require 26 trips (48 experience each + kill the level 5 bull on the way out), doable but still a MAJOR pain in the ass.
Level 6. Only in the Northlands.
Level 7. None.
Level 8. Only in the Northlands.
Level 9. None.
Level 10. The end and 4 of them in the Northlands.
So, that brings us to hunting in the Northlands. It's doable, even solo, but if you're someone (like me) that's trying to see how far you can go without dying.. it's suicide.
I will say this though, the best run I've found for going from 1 to 8 has been the catacombs (a specific run that leads you to a level 5 boss). At level 7, I was getting 18% of my 'experience needed to level' from each run and a run is only 15 minutes long.
..and lastly..
I have a good collection of dye and 1.8 plat from this