The following site goes through the tests available for assertaining if a patient has coeliac disease and explaining what the tests are and what the results mean.
Please click on the bottom of each page on the <next> button to read through all of the contents related to the tests:
labtestsonline.org.uk/under...
(Note: remember that the list of symptoms included are only just a small sample of what a coeliac patient may have or be experiencing.)