I've written a review of a book called
Feng Shui in 5 Minutes. Here is what the author says about desk placement in an office:
Dragon power in the office flows the same way as in your home. The most powerful place for your office desk lies diagonally across from the door, so you face the entrance. If your office has several doors, the best desk position offers the most commanding view of all entrances, while situated as far from all doors as possible. A desk placed in this position becomes a Dragon Desk, giving you added power and zing.
She goes on to say the weakest position for a desk is with your back to the door or doors, near the door.
What type of business are you in? The author has several suggestions for paintings depending on what you're into. For example, water views are great for banks and financial offices.
A rooster feather in your desk drawer is believed to give business a boost.
You may want to note where the prosperity point of Ba Gua is, and add "Celestial Cures" in this area.
Wind chimes, mirrors, live plants, fountains, etc. are all great Celestial Cures.