10to8 will bulk-import your contacts for you for free!
Importing is a great way to start managing customers from a central online location and will also allow you to invite customers to book online.
What you need to do is:
Export your existing contacts into an XLS/XLSX file.
Upload the file by going to "Customers" > "Import Customers".
We usually import the following customer fields:
Name = Customers full name
Email = Customers email address
Phone = Customers phone number
Address = Customers full address
Other custom fields = All other columns with different headers will be uploaded as other information.