Information Overload - where to start

I have a budget, a empty backyard (new construction with minimal landscaping and right now no grass - time of year). I've read so many books, searched the internet, read the forums. I'm feeling overwhelmed. I have my list of plants, a list of prices of different sizes of plants, local nursery prices, mail order prices, and another list that shows plant spacing, and a landscape design for a 110' x 140'. I'm feeling overwhelmed in getting organized in ordering and buying plants. Grass doesn't go in until April but I can plant shrubs and trees now. do I start in the middle and work out?

Help!