Amishah has given you all the answers. To really answer your situation we need more details like if your spouse also have filed for EAD and AP? Did you receive anything from Missouri Benefit Center?
If you filed in August 2004, it is about time for the interview already. Like Amishah pointed out, if you miss the biometric appointment, the case will not be processed until they receive the fingerprints/biometric.
You must have the case number for your spouse's AOS. I would call the 1-800 number to find out what is the status of your case. Of course, you can also make an appointment via infopass to inquire the case in person. If you have moved, you will need to inform them.
Good luck.
Kenmw