A Touch of Magic by Diane Darcy

Nicolette Blair (no, not those Blairs) is an all-powerful witch!

Okay, maybe not, but she intends to be. She might be the least potent witch in her family, and she might be an accountant (hey, D’s get degrees!), but darn it, she has plans!
Her formidable father has given up on her and has set her up as a bookkeeper in town. Then he talked her into an engagement with a strong witch from another clan. (And why did she agree to this? Oh, yes, Daddy issues!)
If she can just find a familiar among her clowder of cats, (yes, clowder) she’ll be able to strengthen her magic and prove herself too powerful for the alliance. In the meantime, she’s made a lot of friends in town and her spells and magic are popular enough to keep her in cat food.
Gavin Graham has traveled thousands of miles to find Isolda Barclay’s grave.
His friend, Declan Barclay (a former ghost himself), is being haunted by the ghost of his long-dead wife. Ever since he’d come back to life upon the moor, Declan has not had a moment of respite. If Gavin has anything to say about it, (and he does) his friend is going to live out his second chance in peace and quiet. They both will.

When things don’t go their way, it’s time to get a second opinion. Luckily for him, there’s a witch in town, and it looks like she’s for hire.