1. A method, comprising: receiving a sample document that includes a text portion; in response to said receiving, automatically generating a visual information metric for the sample document that corresponds to a layout of at least the text portion or to a visual appearance of at least the text portion of the received sample document, wherein the visual information metric is represented by a value for the sample document, the value comprising two or more quantifiable attributes concatenated together into a single value, wherein said quantifiable attributes include balance, contrast, whitespace, grey value, color value, page layout, or combinations thereof; receiving an adjustment to the value, wherein the adjusted value represents a change to the layout or to the visual appearance, wherein the change is relative to the layout of at least the text portion of the received sample document or to the visual appearance of at least the text portion of the received sample document; comparing the adjusted value with predetermined numerical information regarding layout of respective text portions of one or more candidate documents or regarding visual appearance of respective text portions of one or more candidate documents, wherein said comparing identifies the one or more candidate documents that reflect a document having the change applied to the sample document; and transmitting a search result, wherein said search result comprises one or more candidate documents selected based at least in part on said comparison.