Answer: There are many perennials that do well in full sun such as daylilies (Hemerocallis), sedum, purple coneflower, black eyed Susan and tall border phlox; you might also enjoy some bulbs such as daffodils and crocus.
One caution in planting near the shrubs is that both boxwood and azalea are quite shallow rooted. Be careful not to damage or disturb their roots when you plant the perennials. This means leaving ample space between them. It would probably be better for the health of the shrubs to widen the planting bed rather than trim back the shrubs. The reason for this is that the shrubs' roots are generally wider than their branches.
Unfortunately, a northern exposure with added shade from trees is not suitable for tomatoes or the herbs as these are all plants for full sun. Full sun means all day or a bare minimum of six hours of direct sun including the hour of noon.
For a shady site as you described you would have better luck growing shade tolerant plants such as impatiens, begonias and coleus in your containers.
For the west side of the house you would need to grow plants that tolerate hot sun. Soil preparation consists of removing existing grass or weeds (dig them out by hand or use an herbicide containing glyphosate, read and follow all of the label directions) and then loosening the soil down about ten inches deep. Add ample amounts of organic matter such as compost, then level the area and rake it smooth. You should also run some basic soil tests to check fertility and the pH; this will tell you how much fertilizer you need to be using and also whether or not you need to add lime.
Enjoy your gardening this season!
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