Hi Deb –
Do you know what kind of worm is attacking your peaches? My guess is that you are having problems with either the oriental fruit moth (OFM) or plum curculio. Fortunately, both of these pests can be treated with the following products.
Surround WP — a wettable kaolin clay — can be used to deter a broad range of fruit tree pests (and diseases), and will reduce damage by up to 60%. Apply before fruit moths arrive and continue for 6-8 weekly applications, or until the infestation is over. To suppress plum curculio, apply at 7 day intervals throughout the egg laying period (early spring).
Bonide® Citrus, Fruit & Nut Orchard Spray is a safe, one-hit concentrate for common insect attacks and fungal problems. Dilute by mixing 5 fluid oz product with 1 gallon of water. Shake well. Thoroughly spray all areas of the plant, especially new shoots and the underside of leaves. Apply every 7 to 10 days, as needed.
Good luck!