Getting Around Fukushima-ken

If you're in a rush to see Japan, take the Shinkansen (bullet train) from Tokyo (Ueno) to Koriyama (approx 1 hour), then change to the JR Ban-etsu-saisen line to Aizu Wakamatsu (approx 1.5 hours).
If you have more time, personally I would recommend the Tobu line from Asakusa station. The journey takes around 3.5 hours but the scenery is fascinating and there are plenty of heart-stopping cliff drops which the train passes alongside. You could even stop at Tajima for a warming local Tohoku variety ramen.
Bicycle rental at the station is available. Walking around on foot is also possible.
Otherwise there is a bus that leaves the station that goes around Aizu Wakamatsu - enquire at the tourist information centre for bus times and fares.