After Olympic National Park my next stop was the excellent hiking trails of North Cascades National Park. The lodging choices however are limited. Concrete, Rockport and Marblemount are the best options for the north unit (Highway 20) where I visited. There is a lodge in the park but it is somewhat out of hate way and I didn't stay there or see it.
The Mount Baker area (photo above) has some great trails also. If you plan to hike in that area you might want to stay closer to that area (near the park but probably about 100 miles away).
The main hikes I did during my June 2005 visit were Heliotrope Ridge (Mount Baker area) and Cascade Pass trail which were both great. I also walked around the Artist Point area (the same day as the Heliotrope Ridge hike) which was also great. The vistas along the highway are also very nice. North Cascades was quite a wonderful place.
The main guide book I used for finding hikes in the North Cascades was, Don't Waste Your Time in the North Cascades - which was good.