I don't how well-known these are, so I better mention them:
This is a Socionics website with some articles. It is clear it's translated from Russian, but it's understandable. Also, here are the descriptions of the types:
Maybe someone can evaluate how good the information is at this site.
I don't know if you've heard of this, but this is an indirect resource (and a good resource for things other than Socionics); you can type in the address of Socionics websites that no longer exist (or look for older pages of existing resources) and access their information.