The following weapons were used in the film Phone Booth:
Smith & Wesson Sigma 380
A Smith & Wesson Sigma 380 is the weapon planted in the phone booth roof by The Caller (Kiefer Sutherland). The Caller refers to the pistol as "the finest cop-killer money can buy". It is picked up and waved around by Stu Shepard (Colin Farrell). The giveaway that this is a Sigma 380 in 380 ACP, is the front sight, magazine release, and Smith & Wesson writing on the front of the left side of the frame. Also the gun's sight isn't missing; the way the rear sight works creates the illusion of a front sight when aimed. Similar to the S&W ASP. Interestingly, Felicia (Paula Parker) claims that Stu has a "Glock", which he used to kill Leon. Smith & Wesson was actually sued by Glock for copying their design for the Sigma.
Benelli M3 Super 90
A Benelli M3 Super 90 shotgun is used by an ESU officer.
Heckler & Koch MP5A3
ESU officers are seen armed with the Heckler & Koch MP5A3 in the film.
Accuracy International Arctic Warfare
An Accuracy International Arctic Warfare sniper rifle is left in the apartment by The Caller (Kiefer Sutherland) to frame a pizza delivery man for his crimes. As The Caller is seen outside the booth itself, he carries a Storm or Pelican hardcase, much too short to accommodate the Accuracy International AW (However, he said his rifle was a .30 caliber bolt action 700 with a "Carbon 1 modification" and there is a real possibility that it could've been a Remington 700 in an AICS 2.0 folder but, in the end, it's still just a movie). It is therefore highly unlikely that this rifle is the one that shoots Leon, or Stu. It is also worth noting that despite the depicted suppressor, the rifle report is far quieter than you could ever get an Accuracy International AW.
At the end The Caller has a rifle case with him, so what we could assume is that he was actually using a Remington 700, which he took with him at the end and left the Accuracy International AW as a decoy to further convince the police that the dead pizza guy was the shooter.
It should be noted that the aforementioned "Carbon-One Modification" may be a Christensen Arms Carbon One Custom, which is based off of a Remington 700 action.
Every shooter must have noticed the reloading bench found in the apartment of the caller. We can see an RCBS Rock Chucker reloading press, an RCBS Uniflow powder dispenser and a powder scale.