Wow! Sorce remembered me!
There is the
Nebraska Bonsai Society, but there obviously isn't a physical place associated with it. Your best bet to visit a private garden is to contact the NBS on the F
acebook page. A couple members man that and would be able to help. (And if you do end up visiting a private bonsai collection in town, let me know and I'll go with you! I want to meet more NBS members and see their trees too).
When the NBS has a show, it is usually at
Lauritzen Gardens, but I don't think there is anything up now.
I'm just new to bonsai myself, or else I'd invite you to see my trees. And I'm a new member of the NBS and have only attended one meeting and that was online, so I don't have deep contacts.
Most of the bonsai in town, as far as I know, are in NBS members' backyards. There is not any focused nursery support, I've been looking.
Reach out if you have any questions while you're visiting my city!