This old chestnut, probably the most common scenario of all for students to undertake as a project within databases and yet in the vast majority of schools it will simply be taught incorrectly with just 3 tables. You need 5 tables at the core of it to make it actually "work" and this series of screencasts and footage of my and my family badly acting out how a DVD hiring shop works endeavors to explain how to do this project properly.

Note the videos for this project were made a fair few years ago and I use Access 2003 to build the database, however I have not re-done them as there is not really any difference expect the interface design in Access 2007/10. The techniques are basically the same.

cone   film 1 - what data to store? 
cone  vid 1 - simple DVD table
cone  film 2 - don't type it in twice
cone  vid 2 - genre & certificates
cone  film 3 - unique identifier
cone  vid 3 - DVD copy table
cone  vid 4 - customer table
cone  film 4 - break up order table
cone  vid 5 - orders and items
cone  vid 6 - forms part 1
cone  vid 7 - forms part 2
cone  vid 8 - combobox
cone  film 5 - someone forgot something
cone  vid 9 - combobox again
cone  vid 10 - query
cone  vid 11 - compound key
cone  vid 12 - conditional formatting
cone  vid 13 - receipt
cone  vid 14 - adding to the receipt