According to Aryeh Kaplan in his introduction to the Bahir, R Nehunia Ben Hakana is from Ammaus (Emmaus). This is also indicated on the Jewish Virtual Encyclopedia and Wikipedia. None of these sources seem to show where this factoid about Hakana's place of origin comes from. Searches on Sefaria have not been fruitful either. Does anyone know?
This idea is brought by Rabbi Prof. Shmuel Klein in his book "Eretz Yehudah" (Land of Judah), pg. 94, footnote 11 as part of a hypothesis suggested by Avraham Geiger. He refers also to his own essay in "Leshonenu" vol. 1, pg. 338, where he wrote (my translation):
"Ben Hakanah: Nechuniyah...man of Emmahus1 lived during the time of the Temple. It's quite possible that, as was already theorized, he (or his father) was of the sect of the Zealots (Kana'im).2
"שאל תלמיד אחד את ר' נחוניא בן הקנה איש אמהום..."
Translation: "A student asked R' Nechunyah ben Hakanah, man of Emmahum..."
In the footnote on "Emmahum", Rabbi Hoffman noted that it should read "Emmaus".
Note: The Jewish Virtual Library writes that the source for this claim is in Tanchuma on Devarim 26:13, but I've checked both the Buber and regular editions and couldn't find any mention of this there.
1 Not a typo in the essay itself. See Rabbi Hoffman's footnote.
2 In his essay in "Leshonenu", vol. 2, pg. 260, he went back on this idea and concluded that it was more likely that the term "Hakanah" was not a reference to zealous origins, as it's always written with a Heh at the end and not an Alef (קנה and not קנא). He suggests it may have been related to the saying "A person should always be soft like a reed, and he should not be stiff like a cedar." (Taanit 20a); "reed" in Hebrew being "קנה" (kaneh).