Since I assume you do eat dairy, whey protein is used in many many protein powders. If you google whey protein powders you will find a ton of them to choose from. Probably quite a few on your grocer's shelf, too, these days. A protein powder I like the taste of is sweetened with stevia (a natural sweetener), but that stuff is expensive. Supplies of stevia are very limited in this country because of successful lobbying by the artificial sweetener makers.
As for mixing protein powders on the trail, I bring a tupperware shaker bottle. And I've found that if I add the powder AFTER I've got water in the container, that it mixes up a heck of a lot better. Put the powder in first before the water and it wants to lump up and stick to the bottom. (And the suggestion to be sure to rinse out the container well is a very good one.)