Where can i find information about different foods?!

I'm doing UPS in college and we're currently on a fitness programme. We had to list everything we ate throughout the week, including drinks, snacks, dinner/tea, lunch and breakfast. What we have to do is Catagorize each food. for example, if i ate e.g a salad, for my lunch, i'd have to write down weather it's a Protein, Carbohydrate or Fat, also how many calories and kilojoules are in the food...

Does anyone know a website where i could quickly find all this information (food catagory(protein,fat,carbohydrat), calories and kilojoules) ?.

Thanks a lot!