I have been looking into ALT to see if I can get an overview of the 'literature' and came across the TENC project who have assembled standards-based lists of journals and conferences. The lists are very intimidating and although it is easy enough to see which are the main-stream e-learning ones, even those are too many to keep tabs on. Some offer RSS feeds and others email alerts but some do none of that - like http://www.ifets.info/ http://www.ask4research.info/journals.php?lang=en is another collection.
As Chris Jones says, the literature is SO dispersed and diffuse - not just in ALT journals but all over each discipline's educational journals and conferences - so, for example, I recently found a highly relevant article from the Journal of Technology in Human Services!
An esteemed colleague recently said that you stop looking through the literature when you find the same themes emerging but how do you go through all the potential sources without dedicating your entire life to it?!