Big Sky Rancher (Montana Mavericks: Thunder Canyon 1) by Carolyn Davidson

Sassy and opinionated, she was not what he'd expected--but exactly what he needed, in spite of himself.

Lucas O'Reilly did things his way...and as founder and mayor of Thunder Canyon, he answered to no one--and liked it that way. Except lately, now that he owned one of the bigger spreads, and richer mines, under the wide Montana sky, he'd been thinking a wife would be nice. Maybe an agreeable little woman to brighten his house--and warm his bed.

A mail-order bride would be one special delivery, he decided. But what he got instead was a surprise package with a firecracker inside named Miss Jennifer Alston.