ARPA and You Be sure and read through the entire page at the link above.
Even though ARPA does not specifically mention "metal detecting", you need to understand what ARPA says about digging artifacts.
Below is a brief definition of the Nebraska law according to the ARPA law:
Section 82-507 Public land; prohibited acts; penalty; temporary restraining order or injunction.
(1) Any person who knowingly and willfully appropriates, excavates, injures, or destroys any archaeological resource on public land without written permission from the State Archaeology Office is guilty of a Class III misdemeanor. (2) When the State Archaeology Office has cause to believe that a person has engaged in or is engaging in any unlawful conduct prescribed in this section, it may apply for and obtain, in an action in the appropriate district court of this state, a temporary restraining order or injunction, or both, pursuant to the Nebraska rules of civil procedure prohibiting such person from continuing such practices, or engaging therein, or doing any act in furtherance thereof.
Source: Laws 2005, LB 211, § 7
Operative date September 4, 2005 ~Revised Statutes Cumulative Supplement, 2006
In addition to the above mentioned ARPA law, if you are metal detecting in Nebraska, you must be aware of another law,
the National Historic Preservation Act. (NHPA)
As confusing as the above laws may seem, if you are metal detecting in Nebraska,
Do not dig anything that you believe is an artifact, or anything that is older than 100 years.
Especially if you are on any State Lands.
If you want to detect on private property, then be sure you get written permission from the landowner.
For detecting in Nebraska, town, village and city parks, you'll need to check with those local officials.
I cannot be responsible for any outdated laws from the time of this posting.
My home page is all about metal detecting in eastern ghost towns.
Have you tried metal detecting in Nebraska ghost towns?
And remember, pay attention to the laws.