Sorry we cant help bypass passwords. If it is your wireless password consult the wireless routers manual or contact the manufactures support line. If the password is for the actual internet connection contact you ISP.
If you haven't changed your password, since you got it, the password is most likely the WEP key on the back of your router. If that's not it, call your ISP. And if that doesn't help, you could refer to another option ...cough cracking cough... which I am not allowed to go into.