I recently discovered that ikea is really scraping-friendly – they have their categories and products belonging to a category all linked very clean, and the product pages themselves include, as json, the complete product data necessary to display a product somewhere else ( say, on an iPad ). They also feature the assembly instructions linked as pdf and more fun stuff. Just open any product page and browse the source, you will discover a field named "jProductData" which is just what you want.
For the datamodel, I used ohm with redis, which takes about no time to setup and works as advertised.
If you are curious, the source is available at github.