facetime - how can i reset my password?

i recently had to replace my ipod touch 4. i had registered my email address and facetime account on my previous ipod. however, when i try and log in to my facetime account on my new device, i am told my password is incorrect (though i know for sure i am typing in the correct password). how can i reset my password? or delete my account and set up a new account with my same email address? thanks for any help anyone can offer.