See the diagram for airplanes from each airport to Fukushima Airport.
Limousine Bus is operated from Fukushima Airport to Koriyama Station(40min, fee: 1,100JPY). See here for the detail.
To Koriyama Station(郡山駅) (by train)
Take Tohoku Shinkansen(Yamabiko or Nasuno). Here is the diagram from Tokyo Station.
It takes about 80-100 minutes from Tokyo Stations to Koriyama Station.
To each venue
From Koriyama Station to BIG PALETTE FUKUSHIMA
Use a routed bus of Fukushima-koutu(福島交通). Here is the timetable.
From platform #1 of JR Koriyama Station West Gate, take a bus EXCEPT bound for "Shibamiya Danchi via Sakaemachi(栄町経由柴宮団地)" and get off at BIG PALETTE. It takes about 15min. The fee is 300JPY and cash only. You CANNOT use IC catds like Suica. Get on the bus from the back and get off from the front and pay the fee when getting off.
From BIG PALETTE FUKUSHIMA to KORIYAMA VIEW HOTEL ANNEX
On the day of the social event, free charter buses are operated from the venue of the meeting to the venue of the social event in the evening.
From Koriyama Station to KORIYAMA VIEW HOTEL ANNEX
It takes 5 minutes from Koriyama Station by foot. See this map(PDF).