Typing this out in the format that Pokebase offers would look terrible, so here's the table of items and their base powers from Bulbapedia instead.
This table neglects to include TRs, which have the base power of the move contained within. For example, TR71 Leaf Storm has a base power of 130.
Some items have unique effects along with dealing damage. These are shown in the table below.
In addition, all Berries activate for the target when flung. For example, a Pecha Berry will attempt to cure poison, even if the target isn't poisoned.
The items that can't be used with Fling are TMs, Apricorns, Poke Balls, Mail, Z-Crystals, Ability Capsules/Patches, Festival Tickets, Red/Blue Orbs, and Rusted Swords/Shields. There are also some specific combinations that will fail, like Arceus attempting to use Fling while holding a type-changing Plate.