I'm eighteen years old and have lost my birth certificate.
I desperately need it in a couple of days.
How do I go about getting it and what forms of id are needed?

You request one from your state department of Vital Statistics. There will be a form to fill out and a fee. If you can do this in person, it will not take long at all. Otherwise, by mail, can take 5 business days.

I'm eighteen years old and have lost my birth certificate.
I desperately need it in a couple of days.
How do i go about getting it and what forms of id are needed?
Go to your court house... all you need is form of id I think it costs like 15 or 20 bucks.. then they will print it out for you there:)

In some US states, you can only get them from the dept of public records, that is at the capitol of the state you were born, you can go to those offices and normally get one the same day. But by mail you are not going to get one in a "couple of days"