Following You Through Time — Bess McBride

Book Three of the bestselling Moonlight Wishes in Time series, a historical time travel romance series set in England's late Regency/Georgian era

Christopher Mason Denison is lost in time, lost in the twenty-first century. That he remains on his estate which has long since been sold and turned into a tourist attraction galls him even further, but he doesn't know how to return “home” to remedy the situation. And by remedying the situation, he means he must find someone to marry and produce an heir to inherit the estate, not something he ever wanted.
Annie Warner has come to visit Moonglow Castle and make the acquaintance of her relatives, the descendants of Phoebe and Reggie Hamilton. She encounters a sullen man on more than one occasion in the neighborhood who both angers her and fascinates her. His dialogue is formal, his demeanor impossibly arrogant.
That these two are going to fall in love is never in doubt. The question is how...and how can Christopher return home to save his estate.

Book 1 - Moonlight Wishes in Time
Book 2 - Under an English Moon