[Ledasmom]

You might want to ask around and see if anyone you know has an apple tree in their backyard. You'd need to make sure it hasn't been sprayed and that nothing around it has been sprayed with anything toxic, of course. We have a number of volunteer apple seedlings that we cut up for our boys.
The pitted fruits (generally called stone fruits by gardeners) are in the Prunus genus: cherry, apricot, peach, plum; almond, though it's a nut and not a fruit, is in the same genus. There are many crosses between members of this group, plumcots, pluots and such, as well as many ornamental cherries that may not bear fruit or bear few fruits.