There are a few resources on the internet for audio versions of the suttas. If you know of more, post them in the comments below.
- Audio Tipitaka(audtip.com) is a new project to create an audio version of free-distribution sutta translations. You can participate by listening, recording, or volunteering in other ways.
- SuttaReadings.net has dozens of suttas read by monastics and lay teachers.
- Ancient-Buddhist-Texts.net audio section contains hours of suttas translated by Bhante Ānandajoti. Especially notable is the complete audio recording of the Udāna.
- Readings from the Dhammapada by Gil Fronsdal has recordings of Gil Fronsdal reading his entire translation of the Dhammapada.