Flight
The airport you'll want to fly into is SeaTac! We booked our flights through Alaskan Airlines as they were one of the few that offered direct flights to and from STL to Seattle. They have a major hub located in Seattle so it made flights cheaper and easier for us.
Rental Car
Port Angeles is 2.5-3 hours away from the SeaTac airport, which is why we planned on having the wedding later in the afternoon to accommodate anyone who'd like to stay in Seattle. The quickest route is by water, first heading to Downtown Seattle and taking the ferry to Bainbridge Island, but there are routes that include bridges should you not feel comfortable traveling by boat!
Hotel
There are a few hotels in Port Angeles if you'd like to stay close to the venue. There are definitely a fair share of Airbnb's as well should you want something a bit more roomy and homey feeling. As mentioned, staying in Seattle and making the trip to the venue the day of the wedding is an option also!