I'm also a spanish speaker Qt developer and living in Mexico City :D.
I think that there are more spanish speakers Qt developers that it seems but it's just that there was not a central community place in which we can share our thoughts, projects or have a nice conversation. This is happening here in the Qt DevNet thanks to features like groups and local forums. You should check the "Qt Latam Group":http://developer.qt.nokia.com/groups/qt_latam, the "Qt Spain Group":http://developer.qt.nokia.com/groups/qt_spain and the "Spanish Forum":http://developer.qt.nokia.com/forums/viewforum/33.
Also, a while ago I started the website "Zona Qt":http://www.zonaqt.com trying to address this, and we have made some progress, we were able to conform a translation team, provide some basic Qt learning material and solve some questions in discussion forums.
The main response for the site came from Spain and South America, and mexican people aren't as active creating as we're consuming, so I've been missing some local people to spread and collaborate with Qt locally. I think it could be nice to meet us and try to start some projects. What do you think?