If you want people here to help you "get started" with the new area, post a picture of it. If you just want to use the computer, Google perennials or shrubs for pacific northwest, your state, your zone, etc. and you will get all kind of possibilities, including images. Software is not going to be an easy way to get help, since there is a learning curve. My experience with some of it is that it can be very uncooperative in providing "the look" one wants.

You might want to hop over to the perennials, cottage, or hosta forums. If you look, there are many pictures that others have posted that might help you get a feel for what you like. Your area is wonderful for hosta! Good luck!

Pinterest is a great place to start. Pin everything you like, then figure out why. Plant selection is very far from the first step.

Pick up a used copy of the inexpensive classic Garden Design Illustrated by John and Carol Grant, read that.