[In A Dark Light]

Though I haven't read it myself, I would imagine that Alan Moore's 'Jerusalem' counts as experimental fiction.

Recently I have read Jordan Krall's 'Aeon', which felt vaguely Ligottian in its presentation of a city, though not necessarily in any other regard. Also, Thomas De Quincey's 'On Murder Considered as One of the Fine Arts', which could be viewed as being experimental, for its being presented as a lecture being given to a fictional society.