Vine weevil eggs are tiny, as far as I know they are invisible to the naked eye. If you find the grubs, Provado do a very effective treatment that you dilute and water on (I think it's just called Vine Weevil Killer). Also if you find leaves with notches in them, that may be a sign that the adults have been feeding, so it's worth keeping an eye out - but they spend the day in dark corners and are tricky to spot. If you find them, they make a satisfactory crunching sound when you crush them!