The town of Cannon Beach has done an amazing job of keeping an architectural integrity. The weathered cedar shingles and siding that compromise the town's visual theme are almost unavoidable.
As for shops and attraction, the main drag is chock full of small specialty shops selling everything from kites to fine lingerie. There are several small restaurants including the coastally ubiquitous Pig and Pancake.
The beach is pure Oregon coast at it's best. Cool at most times of year, but on a clear day incredibly bright and bracing.
Quick Tips:
For a short day trip, here are my suggestions:
Start your visit with a quick tour through town, checking out the shops and eateries, and stopping to buy a kite. Stick with something simple. Then head to the beach. Haystack rock is always a great photo op as it dominates the south end of the beach. Fly your kite, stroll the beach, chat with other people, and prowl the waterline for interesting flotsam and jetsam.
Next, head back to the main drag for a meal, then explore the town more fully, lingering in the shops and looking for that elusive souvenir.
Best Way To Get Around:
Cannon Beach is 69 miles from Portland on Highway 26(the Sunset). Simply follow the signs. It's best to start early as public parking fills up quickly. The town is best seen by foot, so find that elusive parking and hit the bricks.