The first half of Susan Vreeland's collection (titled ''Then'') consists of nine stories about noted Impressionist and Postimpressionist painters from the perspective of the ordinary people around them. Trouble is, her not-so-still lives of Cezanne and Co. aren't all that colorful from a second banana's point of view. In the semi-fictional ''Winter of Abandon,'' Claude Monet's mistress Alice Hoschedé depicts her lover as self-absorbed, work-obsessed, and totally broke. That's not a portrait of the artist it's a Polaroid. Life Studies's second half (titled ''Now'') is far stronger, offering nine contemporary vignettes about how art with a capital A impacts the lives of a construction worker, an orphan, and other lowercase folks.