Nice topic
First I would recommend 'Little Prince' by Saint-Éxupery.. it is one of my favorite books.
Otherwise, I also recommend reading great comic books.. besides the more 'serious litterature'..
Calvin and Hobbes is one of my fave comic books. <3
A great diary to read is Anne Frank's diary. It is not super tragic in itself.. but it depicts a situation and events that were tragic, and that determined the life of Anne.. But no, the diary in itself is not tragic, it is great, interesting, and she was an ordinary girl, but with extraordianry writing gift depicting their life in hiding and also her own dreams, wishes, goals, day to day life and coming of age. She just became famous cuz of this diary.
Otherwise if you wanna find that kind of diaries I think you have to search the net. Cuz most 'famous' diaries are written by writers/authors and hence they are publicized and hence in a sense 'famous'.
But Virginia Woolf´s diaries I think are veeeery fantastic, and about ordinary events and life and writing.. And after all she wasn't that 'famous'.. She became famous posthumously.
Literature depicting life in earlier centuries: I recommend the odyssey, it is a bit like reading a comic book.. and if one reads it out aloud while reclining in a nice sofa, or one the couch.. and perhaps even with company it is even better as its style is very well suited for loud reading. Also works when one is alone.
Not to mention Don Quijote by Cervantes - it is the work of another true genius.. and gives a very interesting insight in his times and is also highly critical of his society.
I'm particularly interested in old journals/diaries (not biographies) of just an average person(or people) from their time period (if those exist? they must right?). I'm also interested in really good literature set in the past as well (I'm talking early 1900's all the way back to the dawn of humanity for both the journals and literature setting time periods).