The most popular watch models are these two: M800
http://cgi.ebay.com/Watch-Phone-Tri-band-Unlocked-Bluetooth-MP3-Best-Value_W0QQitemZ180326286281QQcmdZViewItemQQptZCell_Phones?hash=item180326286281&_trksid=p3286.c0.m14&_trkparms=72:1234|66:2|65:12|39:1|240:1318|301:0|293:4|294:50

and M860
http://cgi.ebay.com/Watch-Phone-Camera-Unlocked-Triband-Bluetooth_W0QQitemZ180327074239QQcmdZViewItemQQptZCell_Phones?hash=item180327074239&_trksid=p3286.c0.m14&_trkparms=72:1234|66:2|65:12|39:1|240:1318|301:1|293:4|294:50

donkeys ages, mostly from southern China. Try "watch phone" on Ebay.

They should have used bluetooth and a regular phone and made a watch that linked to the phone. That way the watch could be smaller and still retain phone functionality. And if you don't want to wear a big silly watch then you're not without a phone. Combine a phone with a bluetooth earpiece and a bluetooth watch so you can see who is calling, scroll through phonebook (or voice dialling of phonebook) etc.

a wristwatch cellphone