I'm a seasoned wood worker and built my own kitchen cabinets. Let's face it, sure you have to measure accurately and have some patience, but they're boxes after all. They're not that difficult to make yourself. Maybe I just think they're simple because I've built a few. When people get to the range hood cabinet, they tend to shy away due to a fear of angles. There's a site called Lulu.com and a publication called "How To Make Your Own Range Hood Cabinet" by James Lynch. It'll give you the information you need to build your own.
Hard wood plywood • Poplar • Copper sheets
These are some of the cabinets and range hood cabinet/cover I built.