Hey MDK2, I use mwlist.org for Mexican and other foreign station lookups. For example, here's the output for 710 kHz for North America using their "Quick & Easy" link:
http://www.mwlist.org/mwlist_quick_and_easy.php?area=3&kHz=710You'll see all the Mexican stations grouped together.
Even better, register for a free account at mwlist.org, and you'll get logging capability with better access into their station database with more search functionality. For example, here's a look at 710 with all stations filtered out except those in Mexico, automatically sorted from closest to most distant from my location. XEDP is highlighted yellow in the "LOG" column which tells me it's the only Mexican I've logged on 710 so far:

Being able to search for stations along an azimuth path is pretty valuable too when using directional antennas. And this isn't just limited to MW stations, it's also good for LW beacons, SW broadcast stations, etc.