2 Great Ones, including links to other blogs:
*  http://jejulife.net/
*  http://groups.yahoo.com/group/rhymeswithjeju/

General Jeju Sites
*  http://www.geocities.com/TheTropics/3234/main.html
*  http://www.chejuinfo.net/index_e.html

Stuff to do, stuff to eat, hotels, etc.
*  http://jejulife.net/2008/08/24/galbi-seogwipo-jeju-south-korea/
*  http://www.shilla.net/en/jeju/online/experience_tour.jsp
*  http://jejulife.net/2007/12/07/climbing-jeju-style/
*  http://www.virtualtourist.com/hotels/Asia/South_Korea/Jeju_do/Hotels_and_Accommodations-Jeju_do-BR-1.html
*  http://english.tour2jeju.net/main/list.php?menu_id=15

Shopping
*  http://www.gmarket.co.kr/index_eng.asp
*  http://www.nelson.co.kr/FrontStore/iMakePage.phtml?iPageId=1
*  http://www.theshopkorea.com/

Don't forget to check out my joint venture with my buddy Boone:  The Bromance...