Do we live in Middle-earth?

[Zigûr]

Originally Posted by Lotrelf

If we live in Middle Earth, in which age are we?

According to Professor Tolkien in Letters "I imagine we are actually at the end of the Sixth Age, or in the Seventh."

Originally Posted by Lotrelf

While reading Tolkien's books I get a strong feeling that his work was inspired from Hindu Mythology (I don't know about Greek as I haven't read anything about that).

I wouldn't be too concerned about Greek Mythology, as Professor Tolkien's primary interest in this regard would be, I would argue, Norse Mythology. A system of ages occurs in many European systems of belief as well, including early medieval Anglo-Saxon ones, with which Professor Tolkien would of course have been very familiar. Medieval people so named their era as they believed they were living in a 'Middle Age' between the pre-Christian era and the forthcoming Kingdom of God. I suppose a system of ages might be one of those cultural artefacts embedded in the beliefs of numerous Indo-European cultures.

Originally Posted by Lotrelf

All this makes me believe that we do live in ME. Or ME was inspired from our world.

Middle-earth was indeed meant to be "our world." More from the Letters:
"imaginatively this 'history' is supposed to take place in a period of the actual Old World of this planet."
"The theatre of my tale is this earth, the one in which we now live, but the historical period is imaginary."
"I have, I suppose, constructed an imaginary time, but kept my feet on my own mother-earth for place."
Although I believe this was an idea that bothered Professor Tolkien more and more as he got older and noticed that there couldn't be much consistency between this and scientific knowledge of astronomy, geology and so on (the Sun obviously had to exist before photosynthetic plants, for example; nor could the geography of the world change so substantially between the end of the Third Age and now, a time period he considered to be "about 6000 years."