I can't really give you a typical gradient and length, but a weekday after work ride might have me climb 1,500 to 2,000 feet over the course of ~20 miles. Hills are unavoidable in Seattle.

I'll skip the gearing talk, and say it mostly comes down to the engine. I used to hate hills, but my favorite rides included lots of them. I'd do the rides a lot, especially when I got a newer bike that was more fun, and they eventually started getting easier. Then I started doing hill repeats. Climbing never got to be as easy as cruising along on the flats, but I managed to improve a lot. Also, knowing the climbs I do most often, I've figured out how to pace myself and take them at a sustainable effort level.