Ideas needed for half acre backyard landscaping?

I live in Porterville, Ca. (central California) and have half an acre of backyard to fix up. My wife and I want to have a combination of a place to entertain and somewhere to get away and relax. She wants a variety of fruit trees, I want many trees that will provide a forest-like atmosphere, trees where I can throw a hammock onto, look up into the branches and daydream. Our back porch is small and I want to expand it soon into some sort of deck in which we can have barbeque's. Im not interested in a pool or anything...ok maybe a spot for a hot-tub or something. I also had an idea in my head of maybe a gazebo as a focal point but that's not set in stone or anything. Any ideas on what kind of trees, shrubs, plants, etc. that I should be looking into? Oh, probably an important piece of info to know...I have two dogs that love to play back there as well. My wife and I plan on doing all the work by ourselves and can spend a decent amount of money...but not a fortune. The area is a large rectangle where my backdoor is set in the mid-line. I want my guests to see a beautiful backyard as they step out of the backdoor. Any ideas and help would be greatly appreciated!