I first started to look at Erica Baum's art when she did her Card Catalogue series: close-up photographs of old library card catalogues that showed several of the card tabs imprinted or typewritten (and sometimes, for really old cards, handwritten) to indicate subject headings, categories, etc. Several of these photos show the catalogue drawer labels. My favorite of these is "Jersey City—Jesus." Anyway, that was 1997. Erica has done several interesting projects since then, all exploring the visual qualities of language as photographic subjects; words in the visual ambience, just there for the looking. Ubuweb has a pretty good collection of PDFs marking the progress of this art. Have a look.
“The card index marks the conquest of three-dimensional writing, and so presents an astonishing counterpoint to the three-dimensionality of script in its original form as rune or knot notation.” — Walter Benjamin, One-Way Street