When I was nursing my son I found that I really liked shirts with easy access, especially in the first few months when I felt like that's all I was doing. One day while in the store I found a sale shirt that would be a perfect refashion to a nursing shirt. It has elastic at the neck, so it can be pulled down. I even made a nursing shirt tutorial for you!
Don't forget to check out my sewing blog for other projects and tutorials!