I try to buy the unsweetened coconut flakes in the bulk bins at Whole Foods or natural food stores. This is your cheapest option because you can get a pound of flakes (which is a lot) for $2-5/lb). However, I feel your pain about the lack of unsweetened flakes at normal grocery stores. While vacationing in Hawaii, it’s been a real bitch finding unsweetened coconut flakes despite the fact that coconut trees are fricking everywhere! We finally found some unsweetened flakes at the Farmers Market Maui (but they stocked packaged Bob’s Red Mill coconut flakes — not local coconut, nor fresh stuff in bulk bins). Some packaged brands I’ve bought in the past at home are Bob’s Red Mill, Let’s Do Organic, and Nutiva Raw Organic Coconut Chips (but I think Nutiva may have discontinued its line of packaged coconut flakes).