After you turn on your Global Store Status, you will want to make sure that you have also turned on the Collection Store Status for the specific Collection you're looking at. 

Any Collections that are uploaded after you've turned your Store On, will automatically have the Store enabled. For your previously published Collections, you will want to open the Collection and go to the Store section of the Collection Settings tab to locate the Collection's Store Status!

Once you have changed the Store Status for the Collection to On, you can also set the Price Sheet to determine the products available: