You could travel to KC. The national WWI memorial is excellently curated and it seems they have plenty of things going on to commemorate the anniversary as well.

Even if you aren't interested in re-enacting, the groups that participate in events have calendars of what's going on. Very often their events are much bigger than just the military re-enactment portion, and even then the people who are involved are usually very knowledgable and love to discuss their subject. I don't know as much about west coast, but Fort MacArthur has a military event July 13-14 this year which would be a great place to get in touch with some of those groups.