I actually got the shelves at Bed Bath and Beyond for about 25 U$D each. They might be out of commission now, but they are branded with the name Vertigo shelves.
As for tips, I can't say much. Simply make your own accessories, and use what you have. Instead of buying a 50 U$D Candle Hurricane from Pottery Barn, buy the glass, and sand, and candle separately from Michaels for only $10 U$D Total. Instead of buying artificial silk palm plant for 200 U$D, buy a real living Palm tree for 12 U$D at Home Depot.