no sound but clicking noise. please help!

[kmm]

my computer broke and when i got it back i was deleting and uninstalling a few things to free up space. somehow when i uninstalled my logitech quickcam my computer crashed. luckly i knew someome who could fix it. when he fixed it everything worked fine but the sound, and to this say it still doesnt work. i know it's not the speakers because i can hear a slight "fuzzy" noise coming from them. when i start my computer the little speaker does not show at the bottom. i tried going to start-programs-accesories-entertainment then clicking on volume control, but nothing shows/pops up.

i can hear a clicking type noise though, when i am signed on AIM and someone signs on and off.

i'm scared to delete anything and ruin my computer again, so if you know what to do and you are almost positive it should work, you're help would definately be appreciated