Aggie Beth. Yes by all means by a tuner. I wouldn't buy a used one though. Also, make sure it is a Chromatic tuner that covers the full scale with all sharps and flats. Some of the Guitar tuners are set up for standard Guitar tuning, and won't cut it for an Auto Harp.

Also, there are some really great threads on the Autharp which give a lot of great advice on playing, tuning, etc.

Just do a forum search on Autoharp.

JAB