I would also suggest getting at least 2 pairs of shoes and alternating them. They will last longer, and you don't want to go to marathon race day with new shoes, or really anything new. You don't want to find out your new shoes blister your feet on mile 13, or an inseam in your singlet is making you bleed.
And drink some beer every night!
I've been to dinner at Jimmy Buffet's house, and I've eaten it at a homeless shelter. And there's great joy and harrowing terror to be found in both places.