I decided against grass for my new garden too, so I'm laying cheap patio slabs (about £2.50 each from our local builders merchants) with beds for plants round the edges of the paths and patios. I just level the ground carefully and loose lay the slabs. If you want to change things around you can without too much difficulty.

You need space in the garden to admire the flowers and bushes etc. If you don't want grass you'll need another space maker. If slabs are not your thing you could use a membrane with bark or gravel on top, though the dogs may make a mess of those too.

Have a look at pictures on here and get some books out of your local library to get ideas of what you'd like and what you want to avoid.