Whites typically are a short-shank machine (the most common). You can measure the feet you have to make sure. Here's a link to help you with that:
http://www.clotilde.com/pages/which_foot.html
By stippling, I assume you mean that you want to free-motion quilt (FMQ). For most machines, you would use a darning foot. Most of these are what is called a "jumping" foot because they contain a spring that raises the foot with the needle (so you can move the quilt in-between stitches) and then come down to hold the fabric in place for the actual stitch. Some machines have a "floating" foot instead of a "jumping" foot, but probably not the White. (A floating foot has no spring and simply floats lightly on the fabric to allow you to move the fabric, but still provides enough pressure for the stitch to form.)
You can use any generic short-shank foot on your machine. Any sewing machine dealership is likely to carry a generic short-shank darning foot, and you may also find them at places like JoAnn's. Or, you can buy this type of foot online. (All-metal feet are usually better than plastic feet.) Here is a link to one on Amazon:
http://www.amazon.com/Distinctive-Da...dp/B007AUZ2H4/