Unless the the purchased company has a Pervasive DB engine you can use, there is the option of downloading a 30-day evaluation copy of the workgroup engine directly from the source.

Then you can use DBI and DBD::ODBC to access the database, works pretty well IMHO. You can open connections simultanously to the purchased database and your current database, hence moving data in one step.

The only cinch is that you need the database description files (.DDF) to be able to use the SQL interface. Otherwise you will have to resort to dumping table data to disk using the BUTIL utility, and then use perl and substr | unpack to parse the asciifiles, yuck.

So, check if the purchased company used the MKDE interface(bad for you) or the SRE (good for you) before anything else.

Update:
Changed CPAN links.