To get your contacts from your Mac address book into Reesio, you must first export those contacts to a V-Card file, convert it to a CSV file, and then import them into Reesio.
Exporting your Mac Address Book contacts to VCF
1. Open your Mac Address Book.
2. In the Address Book window, select one or more contacts.
3. Click File.
4. Choose Export and then Export V-Card.
Note that only the fields you've chosen to share will be exported.
Converting VCF file to CSV file