Here are the weapons and equipment you can acquire in-game, including their stats. All weapons can be purchased from Ammu-Nation store branches, and will be unlocked by progressing through the main story. Some weapons though, have to be unlocked first by finding them in their respective hidden locations.
Submachine Guns
Name: SMG
Power: 22
Rate of Fire: 55
Accuracy: 40
Distance: 35
Magazine Size: 40
Name: Micro SMG
Power: 21
Rate of Fire: 60
Accuracy: 30
Distance: 25
Magazine Size: 20
Name: Assault SMG
Power: 22
Rate of Fire: 55
Accuracy: 40
Distance: 35
Magazine Size: 40
Melee
Name: Unarmed
Power: 5
Rate of Fire: 20
Accuracy: N/A
Distance: 1
Magazine Size: N/A
Name: Knife
Power: 15
Rate of Fire: 20
Accuracy: N/A
Distance: 1
Magazine Size: N/A
Name: Nightstick
Power: 10
Rate of Fire: 15
Accuracy: N/A
Distance: 1
Magazine Size: N/A
Name: Hammer
Power: 10
Rate of Fire: 15
Accuracy: N/A
Distance: 1
Magazine Size: N/A
Name: Baseball Bat
Power: 20
Rate of Fire: 10
Accuracy: N/A
Distance: 1
Magazine Size: N/A
Name: Crowbar
Power: 10
Rate of Fire: 15
Accuracy: N/A
Distance: 1
Magazine Size: N/A
Name: Golf Club
Power: 20
Rate of Fire: 10
Accuracy: N/A
Distance: 1
Magazine Size: N/A
Handguns
Name: Pistol
Power: 26
Rate of Fire: 40
Accuracy: 40
Distance: 25
Magazine Size: 10
Name: Combat Pistol
Power: 27
Rate of Fire: 40
Accuracy: 50
Distance: 30
Magazine Size: 10
Name: AP Pistol
Power: 28
Rate of Fire: 80
Accuracy: 45
Distance: 30
Magazine Size: 20
Name: Pistol .50
Power: 28
Rate of Fire: 80
Accuracy: 45
Distance: 30
Magazine Size: 20
Name: Stun Gun
Power: 1
Rate of Fire: 10
Accuracy: 40
Distance: 5
Magazine Size: 100
Assault Rifles
Name: Assault Rifle
Power: 30
Rate of Fire: 60
Accuracy: 45
Distance: 45
Magazine Size: 40
Name: Carbine Rifle
Power: 32
Rate of Fire: 65
Accuracy: 55
Distance: 45
Magazine Size: 40
Name: Advanced Rifle
Power: 34
Rate of Fire: 70
Accuracy: 50
Distance: 45
Magazine Size: 40
Sniper Rifles
Name: Sniper Rifle
Power: 96
Rate of Fire: 25
Accuracy: 70
Distance: 95
Magazine Size: 10
Name: Heavy Sniper
Power: 98
Rate of Fire: 20
Accuracy: 90
Distance: 100
Magazine Size: 5
Heavy Firearms
Name: Grenade Launcher
Power: 95
Rate of Fire: 20
Accuracy: 10
Distance: 50
Magazine Size: 20
Name: RPG
Power: 100
Rate of Fire: 5
Accuracy: 10
Distance: 70
Magazine Size: 10
Name: Minigun
Power: 30
Rate of Fire: 100
Accuracy: 40
Distance: 55
Magazine Size: 90
Light Machine Guns
Name: MG
Power: 30
Rate of Fire: 60
Accuracy: 40
Distance: 60
Magazine Size: 50
Name: Combat MG
Power: 32
Rate of Fire: 65
Accuracy: 45
Distance: 60
Magazine Size: 70
Shotguns
Name: Sawed-Off Shotgun
Power: 96
Rate of Fire: 20
Accuracy: 20
Distance: 15
Magazine Size: 10
Name: Pump Shotgun
Power: 67
Rate of Fire: 20
Accuracy: 30
Distance: 20
Magazine Size: 10
Name: Assault Shotgun
Power: 77
Rate of Fire: 50
Accuracy: 25
Distance: 20
Magazine Size: 10
Name: Bullpup Shotgun
Power: 77
Rate of Fire: 50
Accuracy: 25
Distance: 20
Magazine Size: 10
Explosives
Name: Grenade
Power: 95
Rate of Fire: 20
Accuracy: 10
Distance: 15
Magazine Size: N/A
Name: Sticky Bomb
Power: 95
Rate of Fire: 10
Accuracy: 30
Distance: 10
Magazine Size: N/A
Name: Tear Gas
Power: 10
Rate of Fire: 20
Accuracy: 10
Distance: 15
Magazine Size: N/A
Name: Molotov
Power: 50
Rate of Fire: 20
Accuracy: 20
Distance: 8
Magazine Size: N/A
Name: Jerry Can
Power: N/A
Rate of Fire: N/A
Accuracy: N/A
Distance: N/A
Magazine Size: N/A
Armors
Name: Super Light Armor
Defense: 20
Price: $500
Name: Light Armor
Defense: 40
Price: $1000
Name: Standard Armor
Defense: 60
Price: $1500
Name: Heavy Armor
Defense: 80
Price: $2000
Name: Super Heavy Armor
Defense: 100
Price: $2500
Hidden Items and Weapons
Name: Golf Club
How to Get: Go to the Los Santos Golf Club at Rockford Hills. Play some golf and you will acquire one afterwards.
Name: Assault SMG
How to Get: Synch your game with the Rockstar Social Club.
Name: Molotov
How to Get: Located 500 meters south of Hookiees, below the arch of a bridge, which is situated under the first set of streetlights you will see.
Name: Crowbar
How to Get: Head near Franklins second safehouse, go to the pay n spray, then to the closet. Before getting into the garage, climb up the stairs to the right and find the crowbar there.