There's 100+ flights every day from Seoul (Gimpo Airport) to Jeju Island. Korea's low-cost airline Jeju Air sells flights from $35 to $75 (one-way) depending on the time and season.
We're a 10 minute drive (to the East) from Jeju International Airport. You can hail a taxi for roughly 6,000 KRW (or USD $6). You can get Bus 500 or Bus 70 from the airport to bus stop Jeju City Hall for 1,200 KRW (or USD $1).
There's many accommodation options available. There's hotels from $40/night, Airbnb's from $24/night shared to $50/night for an entire apartment and guest house dorms from $12/night. We're also happy to help you find places to stay!