How do I get my old email account back and running?

[Wondering]

I am having a really difficult time getting onto facebook. I had to change my email because the one that I was using was no longer in service. But now when I use my new email, it comes up as someone else...so how do I get my old email back even though the account is closed, and if someone could even help with the facebook problem that would be sweet! Thanks a bunch ahead of time! =)