Form: Name/Location/FC/Costume.
Example: Straked/Tampa, Florida/2621-5096-3365/Classic Brown Wario.
It'll be organized by region, so you might even meet a tournament Wario in your area.
The United States
shaSLAM/Montgomery, Alabama/ Cotton Candy Wario
Lusiris/Grand Junction, Colorado/4596-9454-3113
MorphedChaos/Connecticut/1332-7389-1484
Falchion/Orlando, Florida/3050-7303-5384
Straked/Tampa, Florida/2621-5096-3365
CaptainAwesome121090x/Tampa, Florida/4554-5639-4870/Classic Original Wario or Red & Black Biker Wario
Dynomite/Atlanta, Georgia/4682-8394-3568/Red/White biker Wario
Thunderfoot/Kennesaw, Georgia/ 4682-8601-4719/ Baby Blue Wario
Crash (LocoCoco)/Honolulu, Hawaii/ 5284-4371-0578/Green Biker Wario
stnapknah/Champaign, Illinois/ 0130-1746-2226/ All costumes
7FO/Harvey, Illinois/ 1118-5423-9954
Quik/Chicago, Illinois/0344-8956-4074/ Red Classic Wario
leatherhead93/Salina, Kansas/ 2149-2812-6751/ Classic and Brown Wario
Lil cj/Radcliff, Kentucky/ 0001-2981-8851/ Red & White biker Wario
UnGod /Louisville, Kentucky/ Dependent on the mood and stage
Doedekjin/Shrewsbury, Massachusetts/ Black Biker Wario
Vist/Pasadena, Maryland/3136-6422-1475
drunk3ng0ldfish /New Jersey/ Double Cream Macchiato Wario. (the brown one)
Excellence /New Jersey/1418-6443-5599
Greasy /Ridge, New York/4897-5607-7377
DemonFart/Manhattan, New York/4167-6002-0285
Commander Blitzkrieg/North Carolina/5412-9693-5980/ Classic Original Wario
Blue Rogue/Canton/Ohio/2019 9322 9788/ Blue Biker Wario
Hyper Shadowz/Maysvill , Oklahoma/1547 5010 7044
Bassem6/Lawton, Oklahoma/1461-5877-8758
FattyFatFatso/Norman, Oklahoma/Red Biker Wario
Warioman5780/ Pennsylvania/ 4511-0269-0420/Regular Biker Wario
JokÈ?/South Carolina/3050-7261-1788
Wario Nut/Rapid City, South Dakota/0602-6005-3792
PhantomX/Austin, Texas/1160-9442-9872/ Sailor Wario
dr.mario guy /WACO, Texas/0516-7110-7288/ COTTON CANDY WARIO
Popertop/Houston, Texas/ orange biker wario
BMX/Woodbridge, Virginia/4983-4590-2993/
Vyse (TheTomNookster)/ Washington/ 0903-2401-0799/ WarioWare Orange Wario
Canada
b0wzr!/St. John's, Newfoundland
YagamiDark/Richmond Hill, Ontario/1977-0139-5156/ All classic except Green
Gichan/Toronto, Ontario/ 4468 0645 0264/ All costumes
nasir123/St.Chatharines, Ontario/ 2449-4605-7950
MRbloke/St.Catharines, Ontario/3566-1324-4901/ Lucky Orange Biker Wario
Nickcam/Toronto, Ontario/ Blue Biker Wario
Bellioes/Montréal, Québec/0431-3167-4232
BentoBox/Montréal, Québec/4725-9244-0994
Mexico
Buff/Tampico, Tamaulipas/3050-9218-2154
Australia
Bogoron/ACT/5241-3551-4796
Brazil
Samba Smash?
Pado/São Paulo/5241-3551-4796
Europe
the Netherlands
AKA Europe's Smash Central
Ace55/Amsterdam/ Classic Original Wario (Retired)
Stabman/Roosendaal
Austria
Spadefox/Vienna/1462-1930-5291/ Green Classic Wario
Germany
Eye_of_Wisdom/Cologne/2922-0543-8058/ Standard WarioWare Wario
Sweden
Smashkng/Somewhere near Malmö, Scania/2922-0543-8058/ White Overall Wario
PS I'm not going to correct all the links for the names, just use the member search function on smashboards.