Do you want just the coast or a beach too?
We stayed at Proctor Steads just after the Whit BHol. It is about a mile from Craster fer from where there is a lovely walk along the coast to the ruined Dunstanburgh Castle. There a number of reviews of PSteads, possibly including ours
There are a number of other good sites but all a little back from the beach - mant with reviews in the campsite section of this website. There are not really many sites right on the beach cos of the volcanic sill which runs along the coast thereabouts and blocks out seaviews. We love to be able to have a pitch with a seaview. The coastline is really beautiful when you get to it.
As Bryfert has posted above the beaches at Newton are beautiful, clean white sand with very people about, even at busy times. Just follow the signs to Newton and the "Joiners Arms" - you can turn right or left at that pub to get to lovely beaches. The left hand one has carparking.
What is your outfit? Beadnell Bay Caravan and Camping Club Site is quite near to the beach at Beadnell Bay but it does not take caravans only tents and motorhomes.
The coast, also, tends to be a bit windy if the weather is so inclined.
Have a lovely time
Tim and Cary