Flight
If you are flying, fly into Spokane International Airport. This will be the easiest and closest airport to the venue. Any other airport will be too far away and you will end up flying and completing a roadtrip to get to this wedding. Also look into all different kinds of airlines, allegiant, breeze, delta, American, etc. Spokane International Airport has multiple airlines that fly into it, so don't forget to check all your options.
Travel Note
These are all great options for places to stay for the wedding weekend! Anywhere from Spokane to Deer Park are great spots to stay. Just double check distance from venue to ensure you are comfortable with the distance before booking anything!