Brandon Sanderson is one of my favourite fantasy authors. Considering he was first published (Elantris by TOR) in 2005 he has produced a huge amount of work - often several books a year.
The Stormlight Archives, Sanderson's epic fantasy, is designed to have two 5 book sequences. Presently, we're at number 4 of the first sequence - the first book being titled 'The Way Of Kings.' However, three years before he was published he wrote a first version of the book now titled 'The Way Of Kings Prime.'
Sanderson has now released The Way Of Kings Prime, for free. Also, he has had it read by Michael Kramer and Kate Reading (who read all his other books), and that too is free.
The Way Of Kings Prime - epub, mobi & PDF
The Way Of Kings Prime - audio