Resources can be found throughout the various different areas of the game, below is a map marking the different sections/biomes of the ocean along with a list of the area you are most likely to find a particular resource.
Outcrops
Limestone Outcrops
Found in Safe Shallows, Kelp Forests, Caves, Grassy Plateaus, Underwater Islands, Crash Zone, Sparse Reef, Inactive Lava Zone and Dunes.
Drops: Copper Ore and Titanium
Sandstone Outcrops
Found in Grassy Plateaus, Underwater Islands, Mushroom Forests, Dunes, Caves, Kelp Forests, and Mountains.
Drops: Gold and Silver Ore
Baslt Outcrops
Found in the Blood Kelp, Caves, the Grand Reef, Koosh Zone, Lava Geyser's, Mushroom Forests, and Underwater Islands.
Drops: Diamond, Gold, and Uranium.
Shale Outcrops
Found in Jelly Shroom Caves, Koosh Zone, Mushroom Forest Caves, and Lava Caves.
Drops: Lithium and Gold.
Raw Materials
Copper
Found in the Safe Shallows, Kelp Forests, Grassy Plateaus, Underwater Islands, Crash Zone, Sparse Reef, and Dunes.
Obtained through limestone Outcrops.
Titanium
Found in the Safe Shallows, Kelp Forests, Grassy Plateaus, Underwater Islands, Crash Zone, Sparese Reef, Dunes, Caves, Inactive Lava Zones and also from Metal Salvage (gives you 4x Taitanium when fabricated).
Obtained through Limestone Outcrops.
Silver
Found in Kelp Forests, Grassy Plateaus, Blood Kelp, and Dunes.
Obtained through Sandstone Outcrops.
Gold
Found in the Grassy Plateaus, Underwater Islands, Mushroom Forests, the Koosh Zone, The Grand Reef, Dunes, and Mountains.
Obtained through Sandstone, Basalt, and Shale Outcrops.
Diamond
Found in the Mountains, Mountain Range Caves, Lava Caves, Mushroom Forests, Underwater Islands, Blood Kelp Caves, and the Grand Reef.
Obtained through Basalt Outcrops.
Uranium
Found in Mountains, Mountain Range Caves, Mushroom Forest's, Caves, Lava Geyser's, Underwater Islands, and the Grand Reef.
Obtained through Basalt Outcrops and The Grand Reef Seabed.
Lithium
Found in the Crash Zone, Dunes, Floater Island, Grassy Plateaus, Jelly Shroom Caves, the Koosh Zone, Lava Caves, Mountain Range Caves, Mountains, Mushroom Forest Caves, Mushroom Forests, and the Sparse Reef.
Obtained through Shale Outcrops.
Quartz
Found in Safe Shallows, Kelp Forests, Grassy Plateaus, Underwater Islands, the Crash Zone, the Grand Reef, the Sparse Reef, Blood Kelp Zone, and Dunes.
Salt Deposit
Found in the Safe Shallows, Kelp Forests, Grassy Plateaus, Underwater Islands, Mushroom Forests, the Koosh Zone, Floater Island, the Grand Reef, Sparse Reef, Blood Kelp, and Dunes.
Table Coral
Found in the Safe Shallows, Mushroom Forest, Kelp Forests, and Koosh Zone.
Note: You have to cut it with your knife to obtain it.
Metal Salvage
Found in Safe Shallows, Kelp Forests, Grassy Plateaus, Dunes, Bloop Kelp Zone and the Crash Zone.
Acid Mushrooms
Found in the Safe Shallows, Mushroom Forests, and the Grassy Plateaus.
Creepvine Sample
Found in the Kelp Forests.
Creepvine Seed Cluster
Found in Kelp Forests.
Crash Powder
Found in the Safe Shallows Caves.
Aluminum Oxide
Found in the Grand Reef area.
Blood Oil
Found only in the Blood Kelp Zone and Blood Kelp Caves.
Stalker Tooth
Obtained by dropping Metal Salvage ontop of the Stalker. It has to start biting the Metal Salvage to get a tooth to fall off.
Mercury Ore
Found in the Sparse Reef and the Grand Reef area
Koosh Sample
Found in the Koosh Zone.
Obtained through Koosh Bushes (go up to a bush and cut it with your knife to get a sample).
Note: Is Editble.
Magnetite
Found in Mountains, the Mountain Island, Mountain Range Caves, the Koosh Zone, and in Jelly Shroom Caves (Usually found inside certain trunks of Snake Mushrooms). This biome is usually located deep within the Grassy Plateaus.
Edible Animals
Airsack
Found in the Grassy plateaus, Kelp Forest, Mushrrom Forest, Underwater Islands, Safe Shallows, and the Grand Reef.
Boomerang
Found in the Crash Zone, Sparse Reef, Grassy Plateaus, Kelp forest Caves, the Grand Reef, Koosh Zone, Mountain Range Caves, Underwater Islands, and the Safe Shallows.
Eyeye
Found in the Crash Zone, Dunes, Caves, Koosh Zone, Kelp Forests, and the Grand Reef.
Garryfish
Found in Dunes, Underwater Islands, and the Safe Shallows.
Holefish
Found in the Crash Zone, Mushroom Forests, Mushroom Forest Caves, Safe Shallow Caves, and the Safe Shallows.
Hoopfish
Found in Kelp Forest Caves, Underwater Islands, Koosh Zone, and the Grand Reef.
Hoverfish
Found in Kelp Forests, the Crash Zone, and the Safe Shallows.
Oculus
Found only in Jelly Shroom Caves.
Peeper
Found in the Crash Zone and Safe Shallows.
Reginald
Found in the Grand Reef, the Crash Zone, Mountain Range Caves, Mountains, Spike Plant Caves, Sparse Reef, and the Grassy Plateaus.
Spadefish
Can be found in Mushroom Forests, Dunes, Caves, Underwater Islands, the Grand Reef, Sparse Reef, and the Grassy Plateaus.