I live on the water and need to anchor a wood platform to large stones on the shore. Does anyone know how to go about anchoring into stone?

If you mean how to do secure a object to a large stone, drilling a hole in and fastening a special rod into the stone is done often, next merely a cable around the stone

Be certain the boulder is that heavy as it is very easy to underestimate the action of water on a floating wood platform. You don't want to find out after the fact it was enough to drag the rock. It might be better to call a dock builder to have an expert come look see first.

Thank you for your response. By any chance, do you know what kind of anchor I would need and where I would buy it?

Go to a marine store and ask them about anchor types. Be prepared to tell them the dimensions of the platform and the condition of the bottom under the water where the platfrom is... I would be willing to bet they will nix securing to the rocks on shore idea too.