Arda and Maiar do not seem familiar to me.
Read
The Silmarillion and the various collected letters that Tolkien wrote on the subjects, plus the series of "Unfinished Tales". Basically, Maiar could be thought of as angels in physical form, and Arda is the world created by Ilúvatar (Tolkien's version of God in the mythology he created for his books).
Was Saruman also a Maiar? Wasn he killed or banished?
Yes, he's one of the five Maiar sent to Arda (collectivly known as the Istari) by the Valar to help guide Men. From Tolkien:
"Whereas Curunir (Saruman) was cast down, and utterly humbled, and perished at last by the hand of an oppressed slave; and his spirit went whithersoever it was doomed to go, and to Middle-earth, whether naked or embodied, came never back" - Unfinished Tales, Part Four, Chapter Two: The Istari
Interestingly enough, in the books he was betrayed and his physical form was killed by the "oppressed slave" GrÃma Wormtongue on November 3. That day also happens to be my birthday. ;-)
I am tempted to ask you, "okay, Mr Smartypants, where did the Entwives go?"
Tolkien himself gave no indication. Actually, he wrote in one of his letters "I think that in fact the Entwives have disappeared for good, being destroyed with their gardens in the War of the Last Alliance…"
If Sauron is not dead, then he could run for president. We should do all we can to prevent him from hitching up with Carl Rove.
I think a requirement to hold the office is to actually be capable of making an appearance.