Attached should be screen shots of the items and sizes tables.
I would like any rows from the Sizes table to be returned where the Sizes.SizeCatID = Items.ItemSizes
Multiple items could use the same ItemSizes as print sizes are quite standard.
My thinking is (and feel free to correct it if there is a better way) when the item was pulled from the db, the ItemSizes could be used to pull the data from the sizes table to populate a dropdown that lists the size and price and the selected value would equal the SizeID (key), which could then be used to bind the size and price for the cart, or it could be bound to the card and then pull the information out of the db again for that SizeID (not sure which is the best way here)
By making a column that would correspond to a group of sizes a picture could be printed as would save me from making multiple items of the same picture, but available as different sizes. It would make viewing the available prints cumbersome if someone needed to look at 2-4 images of the same picture just for the different sizes.