Jennifer Wadsworth wrote:Gaia's Garden - a Guide to Homescale Permaculture by Toby Hemenway may be of use to you - he has diagrams for small space food forests in that book.
I got this book for Christmas, and I'm itching to get moving on my tiny food forest. I have planted two apples, a cherry, an almond (crossing fingers for this one!), and two blackcurrants. I also have ordered some native trees: crabapple, pear; and some non-edible nitrogen fixers: alder and laburnum. I'm hoping to nick some raspberry canes off my mother in law in London this week, too!
I also have a few perennial herbs: rosemary, hyssop, chives, oregano, mint, lemon balm, garlic, lavender.
And I have rhubarb and daylily, also edible. My small son and I have started harvesting the daylily shoots this week; we both really like them.
And since we are in the same climate, I can recommend nasturtiums as a ground cover to suppress weeds. Ours self-seed prolifically, and I use the flowers in salads and the leaves cooked in stews (like spinach). And they provide lots of biomass. And look pretty!
But actually, my view on weeds has really changed since I read Gaia's Garden. You can eat most of the weeds in this country, and many of them are nutrient accumulators; I let mine grow, and just chop and drop when they get too tall. I even eat some of them; a few young spring dandelions are good mixed in with a salad, and young nettle tops are a good addition to stews and casseroles, in my opinion.