I think I would always buy organic if it were less expensive. I think the muted colors of color grown cotton are really beautiful.
I am expecting my first baby and have just finished ordering a very basic organic layette for her: 1 shirt, 1 gown, 1 hat, 1 pair handmits, 1 pair booties, 6 receiving blankets (actually, compromised here, 4 of them are 'green' cotton, not organic. And bought 6 because that is what midwife recommended for homebirth), and organic diapers. My goal was to buy little, but organic. The cost still added up really quickly.
For myself I haven't bought organic because of the cost. In fact, my 'summer' maternity clothes all came from target! I used to do a lot of thrift store shopping, but haven't found a thrift store I like since moving to the bay area. I did finally order an organic cotton nursing dress, which I am really excited about.
I think as the baby grows I won't be able to afford to continue to buy organic.