The Torah tells us G-d brought Adam into Gan Eden after his creation from earth (Bereishis 2:15). If this is the case where was Adam created?
ודבר השם אלקים ית אדם מן טור פולחנא אתר דאתבריא מתמן ואשריה בגינוניתא דעדן...
And God took Adam from the mountain of worship, the place from which he was created, and put him in the Garden of Eden
Pirush Yonatan says this refers to mount Moriah, the Temple Mount
Targum Pseudo Jonathan Genesis 22:2, referring to ארץ מוריה, land of Moriah,
land of worship
ואזל יצחק לטוור פולחנא אתר דכפתיה אבוי
And Isaac went to the mountain of worship, the place where his father bound him
Targum on Chronicles II 3:1, bearing in mind that it is likely of different authorship than the Pseudo Jonathan, describes where Solomon built the Temple,
בירושלם בטור מוריה באתר דפלח וצלי אברהם תמן בשמא דהשם הוא אתר ארע פולחנא... ותמן אסיק אברהם ית יצחק בריה...
In Jerusalem on Mount Moriah in the place where Abraham worshiped and prayed there in the name of God, it was the place the land of worship... And there Abraham brought up Isaac his son...
אמר רב אושעיא משמיה דרב: אדם הראשון גופו מבבל, וראשו מארץ ישראל, ואבריו משאר ארצות, עגבותיו א"ר אחא מאקרא דאגמא
Adam's body was created from earth of Babel (which is why it is so low - the depression was created by molding his body), his head from the land of Israel, his limbs from all other countries, etc.
Medrash: Adam was created from earth from all over, so that he (and his descendants; mankind) would be able to decompose no matter where they died.
This composition was then placed in Gan Eden.
The Rambam understands these verses to not be referring to a physical location. In Moreh Nevochim 2:30, the Rambam writes (קאפח translation):
וממה שראוי שתדע אמרם ויקח ה' אלקים את האדם עלה אותו ויניחנו בגן עדן הניח אותו לא עשו פסוק זה ללקיחתו ממקום והנחתו במקום אלא הרמת מעלה מציאותו בנמצאים הללו ההוים הנפסדים והנחתו במצב מסויים
And it is fitting to know about their saying (Bereishis Rabba 16:8) "'And Hashem Elokim took the Man' - He lifted him up. 'And He placed him in Gan Eden' - He set him down" they did not make this verse into a statement of his being taken from a place and being set down in a place, but rather it is the elevation of his existence from among those beings who deteriate and his placement in a specific state of existence
So the verse does not refer to any relocation of Adam after his creation, and he may very well have been created in Gan Eden.
The Malbim in his commentary to Bereishis 2:15 understands that this verse does not refer to any relocation of Adam, as he was already in the Garden (Bereishis 2:8). Rather, וינח refers to leaving something somewhere, as in determining this to be its permanent place to remain. The Malbim understands ויקח, and [Hashem] took him, as Chazal often explain קח אותו בדברים, that Hashem "took him with words," i.e. Hashem explained or convinced him, that this is where he should remain forever and it is where he is meant to be.
I have a secondary source reference for you from Mircea Eliade's 'Cosmos and History', Bollingen, 1959, p 17:
According to the Syrian Book of the Cave of Treasures, Adam was created at the center of the earth, at the same spot where the Cross of Christ was later to be set up. The same traditions have been preserved by Judaism. The Jewish apocalypse and a midrash state that Adam was formed in Jerusalem.
Note: Wensinck, p. 14; Sir E. A. Wallis Budge, The Book of the Cave of Treasures (trans, from the Syriac, London, 1927), p. 53; Oskar Daehnhardt, Natursagen, I (Leipzig, 1909), p. 112; Burrows, "Some Cosmological Patterns in Babylonian Religion," in The Labyrinth, ed. S. H. Hooke (London, 1935), p. 57.
Others on here may be able to link the above up with a primary source for you.