Here is some of the info that I have gathered, it should be pretty much all of the worthwhile bows. I am going to remove the names of the specific mobs which drop them, because its no fun if I did

I'm sure it will be easy to gather just that information on your own, and I dont think its my style to give that much info in such an impersonal manner as a post. Have fun~
Deepsea Bow [20 DMG, 35 Delay]
+3 WIS/INT, +4 SVF/SVC, -2 SVD/SVP, +8 SVM
Weight: 4.3 Range: 150 DROPPABLE
Drops from [X] in [Sirens Grotto]
Crystalline Bow [30 DMG, 40 Delay]
+15 SV ALL. Effect: Spirit Strike (81 DD proc)
Weight: 2.7 Range: 225 DROPPABLE
Drops from [X] in [Velks]
Nemmy's Headseeker [26 DMG, 32 Delay]
+25 DEX, Effect: Firefist (instant cast clicky)
Weight: 3.0 Range: 145 NO DROP
Drops from [X] in [Western Wastes]
Balanced Blackwood Bow [25 DMG, 25 Delay]
+10 STR, +5 DEX/AGI, +15 HP.
Weight: 4.5 Range: 140 NO DROP
Drops from [X] in [ToFS (Dreadfang)]
Searwood Bow [30 DMG, 25 Delay]
+5 STR/STA/DEX/AGI/CHA
Weight: 7.0 Range: 155 NODROP
Drops from [X] in [ToV (Dragonhorn)]
Frost King's Hunting Bow [40 DMG, 35 Delay]
+10 STR/STA, +15 CHA, +45 HP, +20 Mana. Effect: Ensnare (procced)
Weight: 7.5 Range: 250 DROPPABLE
Drops from [X] in [Stormkeep]
Kedgemetal Crossbow [60 DMG, 55 Delay]
+5 STA, +10 CHA, +80 HP, +14 SVC
Weight: 7.5 Range: 155 DROPPABLE
Drops from [X] in [Kedge Keep]