Plug your phone to the computer, start explorer, open
Nokia Phone Browser - Contacts folder

Select all and pull them to a folder on your HDD (e.g. C:\TEMP), it will be the vcard folder.

Close the explorer, and unplug the phone if you want.

In vcardconvert browse the source dir (e.g. C:\TEMP), and an output file somewhere (e.g. C:\VCARDCONVERT.SLK). Click on the "Convert" button.

After converting you can open the output file (e.g. C:\VCARDCONVERT.SLK) in MS Excel or Openoffice Calc or any other similar software and handle or export to your favorite format.