For builds 4.1.15 and above:

You can find the database file at the following location:"C:\PaperTiger PTxxxxx41 Backups"

Note: XXXXX indicates Professional/Basic/Network. It depends on the type of the Paper Tiger version you have. 

For builds 4.1.12 and below:

You can find the backup file at the following locations:"C:\Program Files\The Monticello Corporation\MSSQL.X\MSSQL\Backup".

You can find version 3 database on your harddrive at: Programs files/The Monticello Corporation/*.ptd file. 

You can find version 2 database on your harddrive at: Paper Tiger Single User 2.0/Databasefiles/*.ptd file

If you want or need to send the root database to our tech support team: 
<database name>.mdf 
and <database name>_log.ldf 
If you are a Network user, please also send PTAdmin.mdf and PTAdmin_log.ldf 
You can find .mdf & .ldf files at below location on SERVER system: 
“C:\Program Files\The Monticello Corporation\MSSQL.X\MSSQL\Data”