Jo Ann and Michaels are US craft stores which carry bags of shells (5-15 good, small shells per bag) as well as silk plants, decorative rocks, and sometimes even jumbo Turbo shells. Each month they have printable coupons for 40-50% off one non-sale-price item. Just search Jo Ann coupon or Michaels coupon and print off the most recent one! Starting tomorrow, July 12, Jo Ann has a more rare 50% off one item coupon. You can print there latest coupons here (expires July 18). Michael's current printable coupon is also 50% off and can be found here (expires today, July 11). The shell bags are usually around $4 for a mix-match selection of babylonia, turbo, shark eye, and other shells, some of which are suitable for hermit crabs and some of which are not. If you find a bag for $4 with 15 shells for your small hermit crabs, you only pay $2 with the coupon, only 13 cents per shell! I've recently found the Jo Ann bags to contain more Turbo and Trocha shells than unsuitable shells with slit openings. If you are lucky enough to find a jumbo Turbo shell, they sell for about $10 with 2-3 inch openings. Use the coupon for $4-$5 off which is a better price than you'll find anywhere else!