If you have your heart set on mono green elves, you're going to have to get a few mono colored staples. I don't know how much time and money you want to put into this deck, but here are a few ideas.
Gauntlet of Power,
Caged Sun, and
Emerald Medallion are must-haves. Things like
Wurm's Tooth,
Staff of the Wild Magus, and
Prism Ring are up to your own discretion, though I suggest having them just in case you need to fill some slots before you get all of the cards you need. Some of the staple artifacts are
Gilded Lotus,
Sol Ring,
Lightning Greaves, and
Swiftfoot Boots, as well as the various just amazing artifact creatures. For green, you are going to need some just amazing green cards.
Green Sun's Zenith and
Chord of Calling are your tutors, and
Genesis Wave is just dumb. If you can get them,
Sensei's Divining Top and
Umezawa's Jitte are amazing. Other than that, I feel like I can assume you know the good elves, just don't
forget Eternal Witness is insane. It just is. Hope you enjoy your commander experience!