Just like they prefer their models, fashion-y types often favor work spaces that are minimal, pretty and keep the focus on the clothes.
Markers: Modern, sculptural furniture, black, white, grey and silver, glass, minimal accessories, stacked magazines and photography books, task lighting.
Examples:
Alexander Wang's office (another one of his offices appears below.) I assume the office above is home and the one below is his studio, but who knows? Love the use of the photographer's floor lamp in the photo above. Below, my favorite detail is Wang's use of an old Diptyque candle holder as a pencil cup. Tommy from Specs Appeal actually had the same idea and uses a Method candle holder at his desk.
Monique Lhullier's office by Jennie Abbott, Elle Decor: This photo is from one of my favorite spreads in 2008. It just doesn't get much more chic then this.
Jessie Randall (of Loeffler Randall), Domino: This is definitely a softer take on this look, and I just adore the vintage glass bottles and terrarium. Also love how the art in the background looks like a starry sky. I've been trying to figure out where it's from, and I think it may actually be simply black sequins stretched on canvas, which anyone could do at home.
Stefano Tonchi's home office via The Selby: Love, love, love that desk.Shop this look:
1. Steel Pipe desk, (MoMA Store) 2. Montmartre Table (Jonathan Adler) 3. Waterfall desk circa 1970s, (1stdibs.com) 4. Parson's desk (West Elm) 5. Channing Desk (Jonathan Adler) 6. Sawhorse Work Table (West Elm) 
Clockwise: 1. and 4. I think a sleek task lamp is one of the key markers of this look, and Restoration Hardware's takes on this classic are perfect and somewhat budget-friendly. Rowan and Baxter Pharmacy Task Lamps (Restoration Hardware) 2. Rigid Pleats Lamp: If a task lamp is a bit too blah for you, this adorable little lamp offers a great feminine but tough look. (Anthropologie) 3. Rock Crystal Lamp: I think any kind of rock crystal works well with this look, and makes it a bit more sophisticated. The muted colors, shine and natural origins of this lamp would be perfectly suited for the editor-in-chief's desk at an upscale fashion mag. (Anthropologie) 5. Tolomeo Micro Table Lamp: Although I firmly believe that lots of black and white are necessary for this look, a sleek but brightly colored task lamp gives a much-needed pop and provides a great focal point. (MoMAStore) 
Left to right, top to bottom: 1. Peace hand statuette: I picture this on the desk of a more free-spirited fashion lover. It would also be great for an accessories editor [or accessories lover, like me] who could use it to hang rings, bangles and necklaces. (Jonathan Adler) 2. Mint Julep pencil cup (See Jane Work) 3. Geode bookend (Natures-Emporium.com) 4. and 5. The fashion editor's desk calls for sleek accessories with thoughtful, modern design. Page 1 Tape Dispenser and Muji Stapler (MoMA Store) 6. Helmut Lang's Notebook (circa 1996) (Archie Grand) 7. I think these awesome retro style clocks would keep this desk from looking too sterile. Bonox Clock (Urban Outfitters) 8. and 9. No fashion editor's desk would be complete without a perfect, uniform bouquet of flowers [prepared by her assistant] and a classic designer work tote (to throw at said assistant upon arrival :)] Hopper Wide Stripe Mini Rose bowl (Kate Spade) and Tessuto & Riccamo Tote (Prada). 10. For those of us who can't afford hired help to run down to the florist or flower market every few days, a nice alternative would be a perfect white potted orchid.