Hi
If looking for an obit, try
omahaobits(dot)wordpress(dot)com(slash)

State of NE seems to take awhile, might try USGENWEB>NE>Douglas>Vital records (listed on left)
Am not sure of the speed or if it will be photo copy.

If death is old, might try
www(dot)omahahistory(dot)org(slash)
>collections>genealogy
They have death records for Omaha 1873-1907 and South Omaha (1873-1905)