Umm, this may be a dumb question but are you holding the home button while you press the power button? That will get you into stock recovery so you can wipe data. If you did this nevermind. I'm just throwing suggestions out there just in case your aggrivation is getting the better of you.
I live life by three rules. Rule one, Sh*t happens, rule two, sh*t happens on a daily basis, rule three, get used to the first two.