These boards are produced by Analog Devices and are generally well supported. In the case where both a Stamp and an EZKit exist for the same processor, the Stamp version is highly recommended over the EZKit.
The Bluetechnix guys put together a suite of Tinyboards which are generally well supported as well.
They can be combined with a variety of Evaluation boards and Extension boards.
This Blackfin module is produced by CJSC NII STT