Now you can buy the novella separately in ePub format. Each story is independent of the others, although "The Lost Pathfinder" leads directly into Prince of Wolves. Here's what's available so far:
“A Lesson in Taxonomy”* (in the free Wayfinder #4)
Also check out the other Pathfinder Tales available both free on the Web Fiction tab and in ePub or PDF format in the store. If you like them, please leave a comment or a review.
* Also still available for free at Paizo's Web Fiction page.