The Girl Who Disappeared Twice (2011) by Andrea Kane

Not Kane's first book, but the first one in the Forensic Instincts series.  Casey Woods heads a private investigatory firm that includes a former navy seal and a computer whiz (read: hacker).  Probate Judge Hope Willis 5-year-old daughter is kidnapped from her school.  Hope immediately calls in Forensic Instincts, as well as the local police and the FBI.  Casey's people can take shortcuts that the FBI can't.  The case is further complicated by the fact that Hope's twin Felicity was abducted as a child, and never found.  Woods, her co-workers, and the FBI chase false leads galore until they finally trip onto the correct path.

The writing is a little trite ("Silently, she talked herself down, reminding herself why she was doing this."), but very suspenseful.  The characters are interesting, and the mystery is well-plotted.  I'd have to read her earlier books to tell if she is consistent.

Happy Reading!~