In my Laws of Universe blog, I have installed a free service that when clicked on will read the content of my blog post in a crystal clear voice with no accent.
The service is provided by Odiogo.com
Similarly, Read the Words is a free online service that will read aloud any text you enter. You can upload a file in MS Word, Adobe PDF, HTML, a URL or even RSS Feed!
You can ask the voice to read English, Spanish and French and you are allowed to use several readers.
They say that it takes less than 1 minute to cover 1 hour reading material. You can then download the sound file as MP3!