@ 1420 Peach
You just had to know this was going to happen when you chose that title for your post
. My favorite way to check for completeness is to take an arbitrary monotonic bounded sequence of application items, find its limit and check that this limit exists in our application or its union with our supplementary materials.
Some schools do this computation for you, but each one has a different method. Those who use embark use the online notification system. Others are happy to take calls and confirm completeness over the phone. Others send you automatic e-mails such as MIT and Stanford, though if you saw zxcv's post, Stanford doesn't seem to be living up to its promise.
If any schools haven't given you the confirmation you wanted, then I'd say call the department (or the grad school, if they're the ones who handle materials), and ask "What should I do if I haven't received confirmation?" rather than "Do you have my materials?" since some schools don't want to hear the latter.