Step 1: Selecting your weapon
--Electric assault rifles (M16, M4, STG) Usually around 300-400 fps (feet per second)
--Electric sub-machine guns (Thompson, Mp5, MP40) Usually around 300-350 fps
-- Spring rifles (M14, M4, Dragunov) Usually around 330-450 fps
-- Shotguns (single-shot, multi-shot) usually around 300-350 fps
-- Spring pistols (Desert Eagle, Colt, Revolver) Usually around 250-310 fps
-- Electric pistols (Colt, Desert Eagle, Crosman) Usually 200-275 fps
-- Gas guns, I don't own any and have never used one. The only downside is buying gas. Otherwise, they are powerful guns.
For beginners, I recommend a spring rifle. It is easy to maintain, and easy to figure out. I also recommend having a spring pistol. This is handy for when your run out with your main gun. Another good entry gun, is a shotgun, either multi-shot or single. These are good guns that almost never break.
If you really want to, you can buy an electric gun. These are expensive though, and have more breakable parts. That is why I prefer the spring gun. It is cheap and reliable. But if you do buy an electric gun, I would recommend buying a universal smart charger as well. This way, you can't overcharge the battery and ruin your gun (like I did with my first one).
And please, don't buy a gun case. They are more expensive than the guns below.
The pictures are of some recommended starter weapons. All except the M16. That is my electric gun.