Most credit unions aren't open to the general public, but require some kind of affiliation to become a "member." I'm not sure if I could join one or not, but I'll be checking into it. There's one literally right across the street from me.
In the old days, most of the credit union memberships were based upon employement (although, even there, the name was frequently more limited than the organizations listed). In recent years, many have shifted to a geographical designation.
That being said, one of the larger ones in this area recently converted to a S&L.
Normally, I'd suggest your state credit union association:
http://www.nebrcul.org/
but even the 'contact us' page appears to be password protected.
I think it would be safe to say that any organization that password protects its press releases is being run by idiots. Perhaps you should stay with a bank.
Here's a link that is more helpful.
http://www.creditunionsonline.com/state.php?state=NE&page=0
The credit union here in Colorado has its loophole. If you join a certain consumer group, you gain access to the credit union. The cost to join the consumer group is $5.
consider what you pay in ATM fees and it is a bargain.
Now if you have a bank like USAA which only has one branch, they pay any ATM fee up to $2, They are great except when you want to cash your rolled up change.