How do you program remote transmitter for '99 Alero?

[flooritnfly]

I got mad last night and launched my keys across the room like an idiot, now my remote transmitter for my 1999 Alero does not work. I take pictures of cars for a living and was able to get a new remote transmitter that is for GM and looks identical to my original. I am wondering how do I program it to get it to work? If that is not possible how do I get my old one working again?

I have tried a few methods I found thru Google but they are not working...

Thanks!