The Howling Grotto's pirate ghost caves were one of my favorite hunting spots, especially right after the Nargor update when you could sell red robes for 15k before red cloths dropped down to their current prices. I also liked the atmosphere and creepy decorations, as well as the relative safety of the hunting spot. I usually hunted the big section down a floor with a 3x pirate ghost spawn with summons to save mana when I was a lower level, but at around level 40, I thought just using exori vis (or whatever new element spell now) was a great way to go. The spot wasn't great for making money unless you get lucky with life rings, stealth rings (good luck selling them), red robes, and spike swords. I'd imagine that the new creature products make it much more profitable. 3 backpacks of mana potions should last about 3 hours there. Unfortunately, the space is small and the spawns tend to be slow, so it's not the fastest experience, but you should be looking at around 40,000 experience an hour at a max spawn. That's not counting the new vampire boss who was not there last time I was premium.
There's a bit about the Howling Grotto in the Isle of the Kings library, though I think the book can be found around Nargor, too: http://tibia.wikia.com/wiki/The_Howling_Grotto_%28Book%29