I have been to Krabi twice and each time I have stayed in PraNang Inn. It has a good location being in front of Ao Nang beach and the main road though still quiet and peaceful enough. Best of all the rooms are good and prices are reasonable which you can book online. Do check it out if it suits your needs. If you want something more expensive there is always the cliff and golden beach resort etc.
Picture of the reception area
Picture of my seashell decorated room
Have fun in thailand