Zigbee/Xbee modules available from Digi work on 3.3v and are difficult to interface to a controller. This Zigbee/Xbee Xplorer Serial is very simple to use and using this base board you will be able to connect the zigbee module directly to the PC.
You can also interface the Zigbee/Xbee module to microcontroller for which you will require a MAX232 IC in your circuit. All you have to do is provide a 9-12V AC/DC supply and you are ready to go.
You can use this module for Xbee Series 1, Xbee Series 2, Xbee PRO as well as for Tarang Modules.