I know many brides have shared wonderful sites where they have bought their starfish (thank you!), but I wanted to let you know what I stumbled across today. I was at Home Goods and found a package of 20 - 4" finger starfish for about the same price as all those websites. It equaled out to the same when I would have added shipping, if not cheaper to buy it at Home Goods than the internet. If you have a Home Goods near you, I recommend the trip to see if they have any!
I was also at Garden Ridge and saw 6-7" sugar star fish for $3.99. I know you can find them for a dollar or so cheaper online but if you don't need many you can choose the ones you want and not pay shipping. Me getting them this way prevented me from buying extra just incase they broke and I didn't have to pay shipping.
I still haven't found shells for the same price or cheaper than online but wanted to pass along some other possible options for those who have these stores in your areas!