I found this list on an article dated September 1, 2016 in the World Herald:
Plenty of battles at the top
225-win coaches, Record, Final Year
Tom Jaworski, Creighton Prep 343-92-0 2010
Carl Tesmer, Hastings SC 334-86-2
Jeff Bellar, Norfolk Catholic 330-61-0
Mark Wortman, Elkhorn 327-74-0
Gary DeBoer, Law.-Nelson 319-110-4 2009
Bob Schnitzler, Battle Creek 293-89-7 2000
Tim Turman, Wah. Neumann 283-149-2
Doug Goltz, Falls City SH 277-48-0
Fred Petito, Millard North 276-136-0
Ron Mimick, DC Aquinas 275-107-0
Dan Moore, Ansley 275-107-2 2010
Bob Fuller, GICC 268-140-1
Ken Cook, Adams 260-94-3 2000
Mike Brown, Mullen 252-90-0 2012
Through Aug. 28
Dennis Koinzan, Cross Co. 252-124-2 2009
Marty Hingst, Milford 249-154-2
Fred Bessler, Chase County 248-82-1 2001
Chuck Mizerski, Lincoln SE 247-79-1 2006
Ed Haenfler, Grant 243-66-14 1972
Arnie Johnson, Boone Cent. 239-122-1 2014
Skip Palrang, Boys Town 237-77-13 1971
Mike Lehl, Blair 233-85-8 1993
Jim Puetz, Columbus Scotus 232-98-6 2001
Jon Cerny, Bancroft-Rosalie 229-94-0 2014
Dan Tesar, Tri County 227-137-3 2004
Dick Stein, Chadron 226-111-2 2000
Randy Huebert, Papio 225-116-0
Bill Mimick, Humphrey/LHF 225-151-2