Iloilo International Airport is around 20-30minutes away to the city via taxi (depending on traffic).Taking a ferry to Bacolod could be an experience on its own.That what I did a few weeks ago.
Of course the best advice is to take the taxi.It would cost around 400-500pesos depending on you ability to haggle.But if you are traveling on a budget,here's what you can do.
1.Take the FX (parked in front of the airport) to SM-Iloilo.(50pesos per pax)
2.From SM,take the jeepney to the ferry terminal. (8pesos)
the old Customs Building near Iloilo Ferry Port
PS:Thanks to Peter for the tips.meet my ILOILO GURDIANS Peter and Znarf