sorry but yesterday i injured myself hitting hard a rock under my knee... if you need a guide i can recommend you matteo boffi, he's a friend of mine and he's a really experienced guy even if he's young. you can call him at 3395635629
if you're staying in gressoney you can call Francesco, another nice guide, at 3488144942
but if you have the chance ski with gabbio, he's a legend around here
hope you will have great trips!