provenance - Where are Jews forbidden to speak the name of God

It is commonly asserted that the Jews do not speak the name of God (Tetragramaton) in reverence to the Name. It is even treated as taboo to speak or pronounce, or utter the name.

Yet, in the Bible reverential people are shown as using the name, attesting to the name, swearing by the name, "as YHWH lives..." praising the name, exalting the name, proclaiming the name...

Does someone in Rabbinic tradition prohibit speaking and pronouncing the name of God (the Tetragramaton). If so, where? When was it first prohibitted? Where is the prohibition found, or where was it first documented? What does it say. What are the subsequent rabbinic addresses regarding this. What were the surrounding circumstances to the prohibition? How far back can it be traced historically with evidence?

Please provide citation and if possible translation.

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Note:
All of the quotes I have seen only reinforce God's command to not take His name in vain. They only warn against speaking it falsely, needlessly, disrespectfully or incorrectly.
They never prohibit speaking God's name in ways that God proscribes--swearing by His name, praising His name, proclaiming His name...

This is precisely what I would expect from Jewish sages, men of wisdom and integrity, who would never contradict God's word.

Answer

The Mishnah in Sanhedrin 10 (1) lists those who have no share in the World to Come. Included in these according to Abba Shaul is someone who utters the Divine Name as it is spelled.

See Rambam's commentary on the mishnah where he says,

And [likewise], one who pronounces the name [of God] with its letters, yod, hay vav, hay - which is the explicit name (shem hameforash). And they have already mentioned things besides these, that if one does them, he has no share in the world to come:

See Rashi תלמוד בבלי, מסכת סנהדרין, דף ק"א, עמוד ב' (the prohibition refers to the Name of Hashem of 42 letters) and Tosfos (מסכת עבודה זרה [don't have exact source]) it refers only to the Tetragrammaton.

See the Hebrew Wikipedia article for these and other sources and the English Wikipedia article for other material.