Although a lot of Muslims do say Allah is everywhere, it's not the belief of the Asha'ira... Rather the belief of the Asha'ira is more like, Allah is neither no where nor some where because where indicates a place and a place is created and Allah can't be inside of his creation nor above the creation because that would indicate that there is something below Allah or it indicates that in relation to Allah there is a place (the creation, earth, etc) that he is outside of, and both are not possible... so Allah is no "Where", while still being.....
"Salafis" aka Hanbalis (The majority of the Hanbali Scholars) believe in the Uloo of Allah being real, and that he is in fact over his throne by his dhaat, Seperate from his creation in a Manner befitting his Majesty.