Socionics information is not terribly well centralized, so you need to do some digging and collating to get a reasonable picture of the subject as a whole. Some resources I recommend include
socionics.us and
wikisocion.org. As far as Visual Identification, it is sometimes hyped up into unreasonable versions of the original idea, but it's simply based on the idea that the information metabolism shows itself externally in certain ways, including choices of clothing, stance, facial muscle patterns, and even permanent aspects of appearence that come about as a result of habitually moving in certain ways. It hasn't been boiled down to a commonly agreed upon set of features that specific types have, (and it's not clear it ever will be) but an individual can definitely gain a skill over time of recognizing types visually as they gain more experience typing people (at first by purely non-visual means probably). Because of the nature of VI, posed photos are typically not terribly helpful, since in a posed photo one is specifically obfuscating one's internals and putting on a mask, metaphorically speaking.
If you're already familiar with MBTI, then you have a partial stepping stone into understanding socionics, since the T/F and N/S dichotomies correlate pretty strongly with the same dichotomies in socionics, however the I/E and J/P dichotomies from MBTI don't correlate so well. So if you're an MBTI NF, chances are you're in the socionics NF club as well, (though that's not completely certain) but the question is whether you're a
,
,
, or
. Based on the pictures you gave my best guess would be that you're introverted and rational, so
aka EII aka INFj (I don't like using the MBTI-like names for socionic types, though. It encourages bad mental habits)