Only a few of the DC fans come with connectors already attached click here for a small list.
A few different connectors are commonly used on Fans.
A few types from various manufacturers use WM1720-ND
If you see a part number for a fan with wire leads and have a connector style you were interested in we may be able to attach the connectors. Email email@example.com with the fan number and connector number for more information if it can be done.