Dry is nitrous and some way to increase fuel pressure, usually by tricking the FPR. A wet system adds fuel and nitrous into the intake via a nozzel that mixes the two.
Dont get a cheap $600 nitrous setup if you are not familiar with nitrous. You should get a computer controlled system that can shut itself down if fuel pressure drops and can adjust for bottle pressures. Also you will want a window switch to shut the nitrous off above and below preset RPMs. A bottle heater is also a good idea to make the system more reliable. You will need a blow down tube vented out of the trunk and a purge system is also reccomended to keep the lines clear. A quality setup with the added components should run you about $1300-$1500.
Dont go above a 100 shot untill you become proficient with the nitrouses use.
BTW, the tanks are very expensive to fill and only good for 3 or 4 runs before the bottles pressure is too low.
Nitrous sucks unless its a drag strip only car.