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.
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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.
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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.