I think you can find some just about anywhere...but my favorite is Unjury. You have to get it at (www.)unjury.com. They are super fast at shipping and the powder mixes well in just about everything without a taste!
Pam
I usually just go to GNC and get unflavored whey protein...it's all pretty much the same when it's unflavored. Just the cost varies. Unjury is a really good product too!