Chuncheon Korean Open International Taekwondo Championships
World Taekwondo Federation
Gyeongju Korea Open International Taekwondo Championships
You can also check these websites for updates:
Korean Taekwondo Association
Kukkiwon World Taekwondo Headquarters - This training center and museum is located in Gangnam.
Likewise, MMA is growing in widely popularity in South Korea as well. If your dying to check out some MMA tournaments in South Korea, make sure to check out:
Road Fighting Championship for MMA events.
Korean Brazilian Jiu-Jitsu Open Tournaments - BJJ