Name matching dictionary for finding first and last name variants

Question

I have an application that will store and track visitors. These visitors are created in the system by schedulers(users) as needed when they set up a visit. The problem is that most of the time the only important unique identifiers of a visitor are as follows:

• First Name
• Last Name
• Company Name

The risk of duplicate records existing for the same person is inherent, a scheduler may enter a new visitor record in lieu of searching the system for somebody existing by that name.

When I encounter somebody entering a visitor by the same name I display a warning dialog with various suggestions of who this person COULD be, but then even that is not good enough.

I could enter 'Jim Jones' and this person may exist in the system as 'James Jones' or 'Jimmy Jones'. I see there are name recognition software packages available but they are expensive and certainly more heavy than what I am looking for.

Would anybody know where to find a free or open source dictionary file that I can programatically access to find potential name variants? Software or an online service would be nice but even just a data dump or simple text file might do.

I know even this will not prevent duplicate visitor records, I am just trying to keep that at a minimum so it is not a critical feature.