where can i find a gun in my program or online that shoots and does all that already...in other words...prebuilt
I don't mean to self-promote but I have a package on my site for making guns easily (only for FPS's)including scripts and animated models (along with video tutorials). Aside from that you could check out the FPS tutorial which will walk you through making a basic FPS including weapons, which would be great if you are new to scripting or Unity.