Peter Wilson's article memdesign has a lengthy introductory section on typographic considerations, which is a fine tutorial, written by someone who is aware of the issues as they apply to (La)TeX users. (Memdesign now distributed separately from the manual for his memoir class, but was originally part of that manual)
There's also (at least one) typographic style tutorial available on the Web, the excellent “Guidelines for Typography in NBCS”. In fact, its parent page is also worth a read: among other things, it provides copies of the “guidelines” document in a wide variety of primary fonts, for comparison purposes. The author is careful to explain that he has no ambition to supplant such excellent books as Bringhurst's, but the document (though it does contain its Rutgers-local matter) is a fine introduction to the issues of producing readable documents.