The original Dungeons and Dragons was about killing things and taking their stuff.
Here are generators and tables for that stuff, as well as character trinkets, magic weapons and dragon hoards
5E Tools Guides - npcs | dungeons | treasure | PCs | Theros | worlds | dm's guild
Disclaimer. I'm an affiliate for DM's Guild and I also create a lot of products with random tables on DM's Guild..
Treasure Hoards
hoards | magic items | weird stuff | bodies | pdfs
Redkat's Treasure Generator has more detail on the items and art and includes a variety of mundane items.
Donjon has a treasure generator by CR, and Mithril and Mages has a similar one with the option of more details for gems and art. This one from 1-dot-encounter-planner has a clean interface.
For an option without magic items, 5th DnD's treasure tool returns 4 sizes of loot at once, from "minor personal loot" to "treasure hoard".
Magic Items
hoards | magic items | weird stuff | bodies | pdfs
Donjon has a magic item generator with filters by rarity and type.
For more specific items generate arcane tomes, magic rings and potions
If your players favour convenience then try the 5E Magic Shop or a second version which includes description and location.
Weird Stuff
hoards | magic items | weird stuff | bodies | pdfs
A variety of weird magic items can be found, from potions of gelatinous transformation to the prismatic blade.
Then DnD Speak has interesting books, fantasy drugs and rare art objects
And last is a generator for drawing cards from a deck of many things...
Looting Bodies
hoards | magic items | weird stuff | bodies | pdfs
For individuals then take a look at the individual monster tables of Lady Tiefling for Giants, Hags and everything else D&D
Or for pickpockets, hobbit riddles and mundane loot try items in an NPC's pockets
5E specific are trinkets, more trinkets or mysterious trinkets
PDFs
hoards | magic items | weird stuff | bodies | pdfs
5E has DM's Guild and on there you can find tables with Loot and Fortune with tables for mundane and different monster types.
For a different type of looting try Hamund's Harvesting Handbook, with rules for harvesting from monsters and creating things from them.
Recommendations Please!
I'll keep this guide updated so please suggest generators in the comments or on my Discord server
5E D&D Tools Guides - NPCs & Encounters | Dungeons & Traps | Treasure & Items | Player Characters | Theros | World Building | pdfs on DM's Guild