Sure, Somerville shop owners Jan Stephenson and Amy Appleyard sell yarn and needles, beads and jewelry clasps, rubber stamps and paper. But their store offers more than supplies. For a fee, members can work in the light, airy studio space furnished with roomy tables, comfy couches, and expensive equipment a lone crafter might not want to buy. Take a class, or just ask one of the knowledgeable consultants on hand. Spark is also a popular site for grown-up craft parties. 50 Grove Street, Somerville, 617-718-9132, sparkcrafts.com