Aria (Blue Notes #3) is now available in audiobook from Audible.com! Symphony in Blue (Blue Notes #4.5) should be releasing very soon, and Prelude will be up next in the series. All of the Blue Notes Series books should be available on audiobook by the end of the year.
Just a reminder that, with the exception of Symphony in Blue, all of the Blue Notes Series books are standalones. The stories are interconnected, but can be read in any order! -Shira