Here are the accessories, you can equip up to two, per character. Almost all accessories can only be obtained by defeating monsters in battle, however, there are other methods...
:Commen:
Tusk Necklace - +1 ATP
Small Amulet - +2 max HP.
Venom Charm - Negates the effects of 'poison' for the bearer.
Amber armlet - +1 Int.
Sash - +2 to all speed rolls
Jade Collar - +5 to eva%
Magic Gloves - +2 RP.
Power Bracer - +2 to ATP
:Uncommen:
Black belt - +5 to all speed rolls
sage's ring - +5 Int
ribbon - +5 Hp
Firefly ring - +5 Rp
:Rare:
Golden Amulet - Doubles users HP ( only one per character )
Ninja scarf - +10 to all speed rolls
Indigo pendent - Doubles users RP ( only one per character )
:Ultra rare:
Rune Pendent - +30 to RP, +12 to INT
Bone Wing - +20 to EVA%
Fire God Bracers - 10 ATP, 20 HP
Ultima Band - +30 to HP, RP, ATP, and Int