Girdwood is located about 40 miles from Anchorage. For this reason, we would recommend renting a car, especially if you'll be doing some exploring before or after the events!
That being said, Girdwood is a very walking-friendly town. There is a bus that runs from Anchorage to Girdwood back daily (more information here). Once you get to Girdwood, there is a shuttle that runs from 7 am until about 11:00 pm. More information can be found here
There are many options for housing through Airbnb and VRBO. We do recommend staying in Girdwood the night of the wedding, though as it is a 45-minute drive back to Anchorage.
We know many of you might want to take advantage of the beauty that is Alaska's surroundings. Luckily, there are also many campgrounds nearby. If camping is your style, check out these sites.