Hooray! Lethal Seasons audiobook is now available all over. I've been told it might take awhile to roll out to smaller retailers and subscription services, but it's on the way.
Here are some places you can get it right now:
It should be arriving at Nook Audiobooks soon.
Book 2, Scattered Seeds is in the works. I expect that to be available around the end of October or the beginning of November. Depending on schedules and technical issues, the rest of the books should be coming out every 6 weeks. Yippee!