This is a fun site. It lists over 60000 foods and their calorie counts. http://www.fitwatch.com/caloriecounter.html It is very simple to use and should help you with counting calories.
all foods have calories in, some just have more than others!
The United States Department of Agriculture has a "National Nutrient Database" which contains details of calories and nutrients in many different foods. http://www.nal.usda.gov/fnic/foodcomp/search/
About 10% of the total calories intake.
One plain hamburger from White Castle will have 140 calories in it. To find the amounts of calories in other foods from White Castle, go to the website under "Related Links" for this page.
There are so many types of foods out there, that it really depends on what the food is.
5000 calories
If you want to lower your weight and watch what you eat you can watch how many calories are in the foods you eat. The less calories you eat and the more you burn during exercise and the more weight you will lose.
Dieting sites can explain the number of calories in different foods. If you are looking for information on what calories actually are, a scientific website such as Roth Consulting will have this information. Wikipedia is another good resource to learn about calories.
Depends on the foods you are eating. You can easily do a search for the food, and you will find many sites give you the ingredients; one you will like is mydailyplate.com.
All foods have calories.
There is no such thing as "common foods". Foods are specific sometimes ot certain regions or areas, and there are so many foods out there. Please be more specific in your question, so WikiAnswers can provide you with the best possible answer.
If you have a daily caloric limit that you are aiming for, the best way to keep track of your calories and get ideas on low-calorie foods is on a calorie-counter or weight loss website, where you can enter the food and find out how many calories it contains. There are other diet websites that will provide you with a wealth of information on the best low calorie foods to choose, because they are not all equal in terms of health benefits.