Best place I found for Griff hunting is the SE portion of the zone, more or less. There's a lot of other things to consider though.
First, be sure to check the local vendors. Some people will sell anything...
When you zone in from SF, con a passing animal (I recommend a panther) and a treant to find your faction standing in the zone. If you are non-KOS, you're going to love it. As an Iksar necro I was KOS to the animals, dubious to treants, and of course KOS to the JP residents. If you are KOS to the animals, you can expect wolves and cougars to jump in on you a lot. Wolves were very green to me, but attacked me fairly often, and cougars were aqua (at 60) and did as well. Cougars hit fairly hard too.
Hopefully you're not KOS to these two factions (only 3 in the zone you care about for the purposes of this), you can head out and go hunt. JP has very obvious and predictable monster paths. I hunted often near the dryed up river, as it's a mob highway. Griffs will assist each other if they get close to your pull, but Anacondas will not. Griffawns and griffons both drop the meat. Their drop table is very nice for their level, and I made 60% of an AAXP while spending ~a week meat farming. In that time (about 20 hours) I made ~500pp pure cash, a lot of droppable minor items that sold for a further ~300pp to the gnolls, and 134 meats. Also in that time I looted 63 wings and 47 bloods. Wings are for the ever-nummy Qeynos Afternoon Tea and blood is for HE smithing, I believe. On a server with an economy, you might find wealth in selling these regents.
The griffs also have a rare drop of a +20 wis range item or another +wis earring. I never saw either. You may also see "Griffon Down", which is a no drop item for a nec/sk spear. The anacondas, which I found to be the hardest of the 3, will rarely drop a skin for a no drop JP quest as well. Anaconda meat is uncommon. At your level I would roughly estimate the fawns to be aqua, and the other two to be blue. Anacondas were aqua to me. If they poison, they never did it in the times I played with them.
While I was in JP, a 40th level enchanter hung out with me a few times to aleviate my boredom. She never cast a single spell, except mez 1 time and invis the whole time to avoid agro. She gained 2 levels. You may want to consider dragging a ranger or druid friend along and having him forage you plant shoots while you kill. With a duo, you should be fine.
You will recieve faction hits on killing wolves and panthers. Griffs and anacondas are faction-hit free, but are on the same faction as the cats and dogs. Think Wyverns in CS.
Final note: I recommend moving a lot. Mob density seemed to be an issue. When I killed a lot in one spot, suddenly I would either have a ton of monsters to kill (too much sometimes) or none. Moving in a loose circle worked for me.