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GRR is probably your best option to fly into. It's about 50 min away from the festivities, but it usually has pretty reasonable flights.
Flight
The Lansing airport is by far the closest -- about 30 minutes away from the wedding. However, the flights in and out of this airport tend to be more expensive and more limited.
Flight
Detroit is also an option to fly into, but you're looking at about 1h 45 min to 2h of driving to get to the wedding.