Ariya Sacca
I am transcribing a series of talks by Ajaan Buddhadasa on the "Ariya Sacca", and the transcription can be found here.

Here are the links for the actual talks :-

Introduction to Understanding the Noble Truths - 1MP3
Introduction to Understanding the Noble Truths - 2MP3
Meaning of Noble Truths - 1MP3
Meaning of Noble Truths - 2MP3
Noble Truth of Dukkha - 1MP3
Noble Truth of Dukkha - 2MP3
Noble Truth of Dukkha's Origin - 1MP3
Noble Truth of Dukkha's Origin - 2MP3
The Noble Truth of Dukkha's Quenching - 1MP3
The Noble Truth of Dukkha's Quenching - 2MP3
The Path leading to Dukkha's Quenching - 1MP3
The Path leading to Dukkha's Quenching - 2MP3
Concluding Facts about the Four Ariya Sacca - 1MP3
Concluding Facts about the Four Ariya Sacca - 2MP3/a>

Authenticity
A few years ago I obtained these talks from Santikharo's website at Liberation Park, and began transcribing them. Since then they have been taken down, I don't know why; I have lost contact with Santikharo so cannot give an explanation. Santikharo used to be a monk at Ajaan Buddhadasa's temple, Suan Mokh, in Thailand. As far as I can gather Santikaro would give talks in English under Ajaan Buddhadasa's supervision, and these talks were given in this way. Therefore to my knowledge these are original Ajaan Buddhadasa talks, and I have transcribed them to the best of my ability.