Check out these locations to find the corresponding character. Bare in mind that some characters will not appear until after a certain point in storyline progression.
Ray Ricci - In the square between Casino Imperial and capitol in Cuba. He is a Demolitions/Engineer with an Expert Gun License.
Roy Mancini - At the airport in Corazon de Oro, Cuba next to the second plane, behind the Battaglia Cement Factory. He is a Bruiser/Engineer with a Expert Gun License.
Tommy Cipolla - Corleone Compound, New York (pre-order code required). He is an Arsonist/Medic.
Ray Fogliano - On top of building across from Corman's Drive-In, Florida. He is on the rooftop nearest to the Corrupt Official Joey Katz. He is a Arsonist/Demolitions.
Alvin Uzzano - Northeast of Richie's Tavern, New York. He is a Safecracker/Medic with an Advanced Gun License.
Bernard Uzzano - Inside or near the large crypt closest to the north of the hangout of Almeida capo Jaime Fesser at Goldenrest Cemetery, Florida. He is a Bruiser/Medic with an Advanced Gun License.
Jimmy Lira - Unknown (requires bonus downloadable content). He is an Arsonist/Medic/Safecracker/Engineer.
Leroy Petriboni - Las Palmas, Florida. At the "Jersey's Sports Bar", gambling crime ring on the southernmost island. Approach the building from the east to find a door to a small room. He can be found wandering inside and just outside of that room. He is a Safecracker/Engineer with Expert Gun License.
On these locations listed here You'll be able to find the corresponding weapon.
Level 1 - Pistol: Already available.
Level 2 - Silenced Pistol: Florida, Ryan Roth mission. Found during the mission where he sends you to rescue one of his soldiers.
Level 3 - Delta M1911 silenced : Florida, Mangano's Compound. Search the second floor.
Level 1 - .357 Magnum: Already available.
Level 2 - .44 Magnum Force : When attacking Carmine Rosato's compound in New York, go upstairs in the tiny foyer before you approach Carmine. The Magnum is clearly visible on a desk.
Level 3 - .501 Magnum Enforcer: Cuba, Battaglia Quarry Chop Shop. Look at the map to find the lighthouse and go there.
Level 1 - Sniper Rifle: Already available.
Level 2 - Spitzer Centerfire: Florida, Emilio's packing company. It is located on the rooftop; an engineer is required to cut the fence.
Level 3 - Vintovka SR-98: Cuba, Almeida Compound. On the second floor on a desk.
Level 1 - Shotgun: Already available.
Level 2 - Sawed-off: New York, Corleone's Compound. As soon as you leave the compound through the main gate, go straight forward and turn left. There is a hedge that can be burned with an arsonist. The shotgun is behind there.
Level 3 - Schofield Semi-auto: Florida, Global Storage Chop Shop. On the right side of the island, inside the small warehouse.
Level 1 - Tommy Gun: Already available.
Level 2 - MP38: Florida, Granados Compound. Search the second floor.
Level 3 - Modified AK-47: Cuba, Battaglia Masonry. When you enter a certain room, turn left to find a ladder leading underground. Follow the tunnel.
When You complete each condition set here You'll get the allotted Trophies.
Platinum Trophy - Act like a mobster, think like a Don.
Safecracker (Gold) - Crack all safes.
Executions In Style (Gold) - Complete all execution styles.
It's Only Business (Gold) - Eliminate Hyman Roth.
Organized Crime (Gold) - Control all crime rings.
First Crime Ring (Silver) - Control one crime ring.
750 Sleeping With The Fishes (Silver) - Kill 750 mobsters.
Accept This As A Gift (Silver) - Earn one of each favor.
Bag Man (Silver) - Heist each bank once.
It's Not Personal (Silver) - Eliminate a rival family by successfully bombing their compound.
Last Family Standing (Silver) - Eliminate all five rival families.
Shakedown (Silver) - Control all extortable businesses.
This Thing Of Ours (Silver) - Recruit a full family tree.
Welcome To The Gun Show (Silver) - Collect all level 2 and level 3 firearm upgrades.
100 Whacked (Bronze) - Kill 100 mobsters.
25 Massacred (Bronze) - Kill 25 mobsters.
250 Iced (Bronze) - Kill 250 mobsters.
500 Empty Suits (Bronze) - Kill 500 Mobsters.
Ambush (Bronze) - Eliminate four rival families.
Bank Job (Bronze) - Heist your first bank.
BlackHand Brutality (Bronze) - Kill 25 mobsters only using BlackHand attacks.
CIA? DOA (Bronze) - Kill Henry Mitchell.
Contract Killer (Bronze) - Eliminate 5 made men with the appropriate kill condition.
Double Crossed (Bronze) - Eliminate two rival families.
Enforcer (Bronze) - Complete 10 execution styles.
Five Crime Rings (Bronze) - Control five crime rings.
Fortified Venue (Bronze) - Max out all guards at a venue.
Full Of Lead (Bronze) - Kill 150 mobsters only using firearms.
Getting Made (Bronze) - Recruit your first soldier.
Gun Smuggler (Bronze) - Find a level 2 firearm upgrade.
Let Me Upgrade You (Bronze) - Upgrade one of your made men's skills or weapons.
Lockpicker (Bronze) - Crack five safes.
MobFace (Bronze) - Create a mobster using MobFace.
Modified Firepower (Bronze) - Find a level 3 firearm upgrade.
Paying Tribute (Bronze) - Unlock all safehouses.
Pulling The Strings (Bronze) - Send your men to attack a venue from the Don's View.
Right Hand Man (Bronze) - Promote one of your made men to Capo.
Second In Command (Bronze) - Promote one of your men to Underboss.
The Counselor (Bronze) - Accept Tom Hagen as your Consigliere.
Three Crime Rings (Bronze) - Control three crime rings.
Torch The Joint (Bronze) - Send your men to bomb a venue from the Don's View.
Vendetta (Bronze) - Eliminate three rival families.