Atocha train station floor plan

I couldn't locate one, either, sorry. Not sure what your concern is, but I can tell you that all signs are in both English and Spanish, and every information desk has someone that speaks English.

http://img17.imageshack.us/img17/1233/1atocha.jpg The yellow line shows the path for passengers taking the AVE. Number 5 is the entry to the departure area. You put your bags through the security scrreening to enter. They will post the departure gate and start boarding around 15-20 minutes ahead of departure time.

I guess that link does not actually get you there. Try this one: http://www.espormadrid.es/2010/12/plano-esquema-general-de-la-nueva.html and click on the area of the map to enlarge it and get the view I posted above.

Nancy and Lola have given you great information. I would have found it helpful to know in advance that the departure gates are both upstairs and downstairs. There is security screening on each level, so your only challenge is to watch the signs for when your gate is posted, and be on the level where that numbered gate is located. It's possible you may be able to get the gate information ahead of the actual announcement, and can go through security and wait on the interior. Once you have gone through the ticket check procedure at the gate, you will either walk out on the platform to your train, or you will walk down a ramp from the upstairs gates to get back to the platform level, and on out to the train. They really do only take about 20 minutes from official announcement to departure. And keep in mind, you manage your own luggage.

I do not think all the signs are in English. As Ginny describes, there are upstairs and downstairs departure areas for the AVE trains. As I recall, the lighted board outside the security screening zone that tells you where to go is only Spanish. For most of the AVE trains you will go upstairs. For others (like Toledo when we were there), the board will say "Planta Baja" so you stay on the lower floor. Each level has numbered gates that you go through to reach the trains. It is almost like boarding an airplane. If you depart from the upper area, you ride an escalator back down to track level.