i have written a pretty cool song..and a friend of mine has a mic, which i can plug into my macbook. My question is , whats the bets software for recording it..and also editing it?
But why don't you start with Garage Band, as it is free and does what you want to do quite easily. No need to go the advanced route if you just want to do what you want to do, unless you have experience (months and years) with professional software.
Garageband is very powerful, yet so simple to use, that I have no desire to use anything more powerful.
I do like to use it in conjunction with Audacity, which is freeware recording software. I use Audacity to master my recordings. During the mastering phase, I'll apply some compression and trim the beginning and ending (making sure I have the desired amount of silence at each end).