This article on the Yonhap website is worth a look describing the professional rivalry between two Kim Jong-il lookalikes Kim Young-sik and Bae Eun-sik.
Of the two, Kim Young-sik appears to be the better known, at least outside of Korea. He has been featured in an Australian TV news item and also in an article by Barbara Demick for the LA Times.
Update: later coverage in the Guardian and News.com.au