http://www.paullynch.org/eqguide/guides/heros-forge/ http://everquest.fanra.info/wiki/Hero's_Forge Easiest place - The Bazaar
For the 6 main sets mentioned on that page, they all say level 10+ mobs, but there must be a cap to the level that will drop them. Years ago I got the occasional drop, but I was lower level (80s, low 90s, etc). I now haven't seen one drop in about two years, but I hunt in zones for level 100s.
There have been exactly 3 pieces in the Xegony bazaar for over a month all from the same people. I tried hunting the level ranges or hit zones with my Alts and nada.
It's been a while since I did it BUT. I believe the Beryl Hero forge has trivial loot code applied and ONLY drops in hotzone flagged zones. It's a royal pain in the to farm if you are achievement hunting. The droprate also isn't that good even when requirements are met. Godspeed.
The trivial code means the mobs have to be ?light blue? or higher in con in order to drop the item. Sorry, It's one of the areas I have very little knowledge of since I didn't play on FV during its inception and it has so few applications in the game I'm afraid. You CAN shroud down and kill a low level hotzone by using damage shields and get around it but that might not be any faster (it wasn't for me and I never finished Beryl as a result).
This is the info that was in the links I posted. As you can see it has to be current hot zones not just those designated hot zone and at least level 10. Good luck. Beryl Hero's Forge ornaments can now be obtained from light-blue difficulty NPCs in Hot Zones. Beryl: drops from level 10+ NPCs in hot zones Beryl Hero's Forge - Any level 10+ NPC in a current Hotzone