I've posted a number of green smoothies (my original recipes--taste-tested!) in my blog here:
http://thecathenation.com/forum/blog.php?b=1595 (which also has tips for making them), but here's a basic one:
1 frozen banana
8-12 oz. coconut water (depends on how thick you like it)
1 1 1/2 cups frozen blueberries or mixed berries
1 large handful baby spinach
sweetener of choice (taste and see if it needs sweetening---always take two sips, as I find the first one just gets your taste buds ready. Be sure to 'chew' the first few mouthfuls, or at least swish them around in your mouth, to start the digestion process). You could use stevia, Lo Han Kuo/Guo , agave, etc.
If it tastes too 'green,' add a squeeze of lime (I like lime with blueberries) or lemon
This is my own recipe, not from the book.
I do have the book, and it has interesting info along with recipes (though I think Victoria Boutenko's book has better info as to the health benefits. I also think Boutenko's suggestion for rotating greens is better than Openshaw's suggestion for using lots of spinach). I haven't tried the recipes yet, but they look unique (some combos I wouldn't think of, and ingredients I don't usually use, and I can't vouch for the flavor. They must be good if her kids drink them!).
She gives a basic template for making 8 cups of smoothies 2 servings), along with about 50 specific recipes.
If you do a search for "green smoothie recipe" online, you'll find LOTS of free recipe ideas. And youtube has videos showing how to make them (some by Green Smoothie Girl herself).
If you start with a few recipes (no book needed!), you'll soon find yourself getting the feel of it, and coming up with mixes YOU like. After I'd been doing a daily green smoothie for a couple of weeks, I'd wake up thinking about what combos would be good together, and I could almost taste them (that's how I came up with a peach-cilantro smoothie).