I got proof too!
On archive.org www.looneytoons.com pre-dates www.looneytunes.com by almost a year:
05 December 1998 -- https://web.archive.org/web/19981205160358/http://www.looneytoons.com/
TM & © 1998 Warner Bros.
17 January 1999 -- https://web.archive.org/web/19990117031349/http://www.looneytunes.com/
TM & ©1999 Warner Bros. TM & ©1999 DC Comics
Even better, the whois:
Registrar: MARKMONITOR INC.
Sponsoring Registrar IANA ID: 292
Whois Server: whois.markmonitor.com
Referral URL: http://www.markmonitor.com
Name Server: NS.WARNERBROS.COM
Name Server: NS2.WARNERBROS.COM
Name Server: NS3.WARNERBROS.COM
Status: clientDeleteProhibited http://www.icann.org/epp#clientDeleteProhibited
Status: clientTransferProhibited http://www.icann.org/epp#clientTransferProhibited
Status: clientUpdateProhibited http://www.icann.org/epp#clientUpdateProhibited
Updated Date: 09-oct-2014
Creation Date: 11-nov-1997
Expiration Date: 10-nov-2016
Registrar: MARKMONITOR INC.
Sponsoring Registrar IANA ID: 292
Whois Server: whois.markmonitor.com
Referral URL: http://www.markmonitor.com
Name Server: NS.WARNERBROS.COM
Name Server: NS2.WARNERBROS.COM
Name Server: NS3.WARNERBROS.COM
Status: clientDeleteProhibited http://www.icann.org/epp#clientDeleteProhibited
Status: clientTransferProhibited http://www.icann.org/epp#clientTransferProhibited
Status: clientUpdateProhibited http://www.icann.org/epp#clientUpdateProhibited
Updated Date: 11-dec-2014
Creation Date: 12-jan-1999
Expiration Date: 12-jan-2017
That's a good one, there. I grew-up watching the old Looney Toons in the early 70s and vividly remember it being "Toons" as in "cartoons".