I'm a landscape architect. I suggest going to the library and looking at the garden design books, making copies of the designs that you like. You'll probably notice stuff that you like over and over again. That'll help narrow down your ideas. You can go out and buy a few magazines, too, and cut out pictures that you like.

I wouldn't count on your husband's co-worker UNLESS you are willing to be a client (and pay him). We do have to make a living and we always get requests for free design work.

My advice would be to keep it simple if you decide to do it on your own. Choose a limited palette of plants that work well together and for your site (water, sun/shade, etc.) You may want to take the sustainable angle--low water needs, wildlife habitat, non-invasive plants, year-round interest. Or you may not.

The good thing about landscape design is that you can always change it as you learn about what you like in terms of design and plants. Landscapes evolve with you, it's nice.

Do you live in College Station? If so, perhaps you could hire a landscape architecture student from A&M for design work. Please be sure to pay them, though!