I like buying online. Quilt shops are great and I like chatting with the employees, but they're not going to have every single fabric I want. We have a very small quilt shop in town (it actually was a large tool shed converted into a shop) so I have to go outside of town for more variety and the nearest one is half an hour away. Right now I need quite a lot of different Moda marbles and only one of the shops I regulary go sells them...I spent an hour or so picking out every Moda Marble they had, but they had only four of the colors I needed (okay six, but that's only because I found two purples that were a close match and gave into not being picky since I only needed an 1/8 of each).
So I've been buying a lot of Moda Marble fat quarters from a user named anielia for $3.68 (includes shipping) a piece. I've had no problems and has a very good reputation overall (in the past 12 months, only 5 negative reviews compared to almost 5000+ positive). I think a few of the green fabrics I bought for Joe's future quilt came from her, too.