The Dragonslayer's Sword is the first of a four-book series by Resa Nelson. and is currently free at
AMazon.com. The second book is also on sale for $0.99 and the other two are $4 each, so you can get eh whole set for less than $9 if you so desire.
I grabbed this series at least in part from a bundle a couple years ago and enjoyed them quite enough to put in my reread list.