Bernadette, meanwhile a lot of free ABC software exists, as listed on http://abcnotation.com/. The problem with guitar tabs is that a given note can be played on more than one string, leading to a different tab representation. This is how I would proceed: download MuseScore and enter your ABC text there (- it uses a web service). Switch to "guitar tab" and let your guitarist adjust the positions and fingerings.

I think there are several dedicated, non-interactive programmes available, but your guitarist may not be happy with the results.

What sort of guitar music do you have in ABC?