I'm researching my husband's last name, are any of you knowledgeable about where to find trustworthy info?

I’ve been researching my husband’s last name (Scottish origin), off and on for the last year or so, and I purchased our “supposed” coat of arms and tartan pattern. Now, I’m finding conflicting results, on different websites, each claiming that our surname belongs to a different clan.

Does anyone know of a reliable source to find correct information on which clan your surname truly comes from?