accidentally deleted settings button

you cant delete the settings icon it wont let you

Possibly moved it to another screen, into a folder etc.
But it really won't let you delete it as no default icon has the X on it to delete when in edit mode.

Can always try to sync phone again.
If doesn't fix, then restore it.

He's right there's no way to delete it. Perhaps you managed to put it in a folder or something. On your main home screen push the Home button and you will go to a search screen. type in settings and it. See if it finds it. If it does, you can launch it from there but unfortunately it won't tell you where it is.