Did some Research & assembled some Info about Weapons in Counter-Strike Source...
Hope I covered every thing  :
_______________________________________________________________________

KNIFE:

Standard Issue Navy Seal Knife
Nickname: Knife

Damage Primary – 35
Damage Secondary – 50+
Speed Primary – Fast
Speed Secondary – Slow
Price - Free

PISTOLS:

H&K USP Tactical .45 (KM Tactical .45)
Nickname: USP

Damage – 17
Damage(silenced) – 15
Ammo Capacity – 12
Accuracy - Good
Speed - Ok
Price - $500/Free
Secondary Fire - Silencer

Glock 18 (9x19 Sidearm)
Nickname: Glock

Damage – 12
Ammo Capacity – 20
Accuracy – Great
Speed – Very Fast
Price - $400/Free
Secondary Fire – 3-Round burst

MR Desert Eagle .50AE (Nighthawk .50AE)
Nickname: Deagle

Damage – 40
Ammo Capacity – 7
Accuracy – Ok
Speed - Slow
Price - $650

Sig Sauer P229 (228 Compact)
Nickname: P228

Damage – 19
Ammo Capacity – 13
Accuracy – Good
Speed - Very Fast
Price - $600

FN Five-SeveN (ES Five-SeveN)
Nickname: 5-7

Damage – 14
Ammo Capacity – 20
Accuracy - Perfect
Speed – VeryFast
Price - $650

Beretta Elite (.40 Dual Elites)
Nickname: Dualies

Damage – 18
Ammo Capacity – 15x2
Accuracy - Horrible
Speed - Fast
Price - $650

AWARDS

- Good Pistol for beginners: USP

I chose the USP for this category because the USP is powerful, stable, and easy to handle. Don't get me wrong it is still hard to use.

- Good Pistol for snipers: Desert Eagle

I chose the Deagle because Snipers have to get away from people with assault rifles, so this gives people some stopping power

- Best Pistol: Sig P228/9

I chose the p228 as Best Pistol because it is everything in one, good power, good speed, good capacity, good accuracy.

SHOTGUNS:

Benelli M3 Super 90 (Leone 12 Gauge Super)
Nickname: Pump

Damage – 80+
Ammo Capacity – 8
Accuracy – Good at close range, Bad at long
Speed - Slow
Price - $1700

Benelli M4 (Leone YG1265 Auto Shotgun)
Nickname: Noob Cannon, Auto Shotty

Damage – 50+
Ammo Capacity – 8
Accuracy – OK at close range, Bad at long
Speed - Slow
Price - $3000

AWARDS

- Best Shotgun – Benelli M3 Super 90

- Great Power, 1 hit kill headshots, cheap, and you don’t get called a noob if you use it!

SUB-MACHINE GUNS:

Steyr TMP (Schmidt Machine Pistol)
Nickname: TMP

Damage – 10
Ammo Capacity – 30
Accuracy – Good at close range, Bad at long
Speed - Fast
Price - $1250

Mac M10 (Ingram Mac-10)
Nickname: Mac10

Damage – 13
Ammo Capacity – 30
Accuracy – Good at close range, Bad at long
Speed - Fast
Price - $1400

H&K MP5 Navy (KM Sub Machine Gun)
Nickname: MP5

Damage – 13
Ammo Capacity – 30
Accuracy – Great at close range, OK at long
Speed - Fast
Price - $1500

H&K UMP (KM UMP45)
Nickname: UMP

Damage – 16
Ammo Capacity – 25
Accuracy – Good at close range, Bad at long
Speed - Medium
Price - $1700

FN P90 (ES C90)
Nickname: P90

Damage – 13
Ammo Capacity – 50
Accuracy – Good at close range, Bad at long
Speed – Very Fast
Price - $2350

AWARDS

- Best SMG – FN P90

- Fast, long clip, did I mention fast?

- Best SMG for Noobies – Mp5

Ive played CS for a long time now, and Ive seen the MP5 get worse, but with source, it got a lot worse. But still a good gun for noobs lol.

ASSAULT RIFLES:

GIAT FAMAS (Clarion 5.56)
Nickname: FAMAS

Damage – 20
Ammo Capacity – 25
Accuracy – Near Perfect
Speed – Fast
Price - $2250
Secondary Fire – 3-Round burst

IMI Galil (IDF Defender)
Nickname: Galil

Damage – 22
Ammo Capacity – 35
Accuracy – Ok
Speed – Very Fast
Price - $2000

AK-47 (CV-47)
Nickname: AK

Damage – 27
Ammo Capacity – 30
Accuracy – Ok
Speed – Fast
Price - $2500

Colt M4a1 Carbine (Maverick M4a1 Carbine)
Nickname: M4  (My Fav)

Damage – 22
Ammo Capacity – 30
Accuracy – Great
Speed – Fast
Price - $3100
Secondary Fire – Silencer

Steyr Aug A1 (Bullpup)
Nickname: Aug

Damage – 22
Ammo Capacity – 30
Accuracy – Great
Speed – Fast
Price - $3500
Secondary Fire – Scope

Sig 551 (Kreig 552)
Nickname: Sig

Damage – 22
Ammo Capacity – 30
Accuracy – Great
Speed – Fast
Price - $3500
Secondary Fire – Scope

AWARDS

- Best Rifle – M4a1

- Very stable, accurate, powerful

- Best Rifle for Noobies – M4a1

- Spray, Pray, headshot, reload.

- Best Rifle for Headshots –Famas

- Put on the 3-rnd burst, aim high, and they are dead.

- Best Rifle with scope – Sig 551

- Better than AUG because it looks better, thats pretty much it.

SNIPER RIFLES:

Steyr Scout (Schmidt Scout)
Nickname: Scout

Damage – 63
Ammo Capacity – 10
Accuracy – Perfect
Speed – Fast
Price - $2750
Secondary Fire – Scope

AI L96 Arctic Warfare (Magnum Sniper Rifle)
Nickname: AWP

Damage – 100+
Ammo Capacity – 10
Accuracy – Good
Speed – Slow
Price - $4750
Secondary Fire – Scope

Sig 550 Sniper (Kreig 550 Commando)
Nickname: 550

Damage – 50
Ammo Capacity – 30
Accuracy – Good
Speed – Very Fast
Price - $4200
Secondary Fire – Scope

H&K G3 SG1 (D3/AU-1)
Nickname: G3

Damage – 65
Ammo Capacity – 20
Accuracy – Good
Speed – Very Fast
Price - $5000
Secondary Fire – Scope

AWARDS

- Best Sniper Rifle  AWP (I dislike it)

- Very controversial, but you can’t beat it.

MACHINE GUNS:

FN M249 Para (M249)
Nickname: Para

Damage – 23
Ammo Capacity – 100
Accuracy – Bad
Speed – Very Fast
Price - $5750

-----------------------------------
Hope it's useful for Beginners that are new to this, & Pro's who would like to revise their info