National Dance Council of America

http://www.ndca.org/

Official governing council of dance and dancesport in the USA

USA Dance

http://usadance.org/

Official organization for amateur dancers in the USA

Csilla Designs

http://www.csilladesigns.com/

custom couture ballroom and latin dance costumes; pre-made and rental dresses also available

Showtime Dance Shoes

http://www.showtimedanceshoes.com/

Great selection of top quality ballroom and latin dance shoes

DanceShopper

http://www.danceshopper.com/

Everything you need for ballroom and latin dancing: shoes, practice wear, music, jewelry, cosmetics, and more

BallroomDancers.com

http://www.ballroomdancers.com/

Dance forums on almost every dance topic imaginable, plus classified ads for partners and costumes

Ballroom Beats

http://www.ballroombeats.com/

Ballroom and latin dance music on demand

Biggest Girl in the Ballroom

http://dancingwithstefanie.com/

a funny and touching blog about one dancer's journey as an amateur competitive dancer

Cloud Cray's Ballroom Junkie blog

http://ballroomjunkie.blogspot.com/

Cloud Cray's Ballroom Junkie blog -- ballroom humor and insight full of fun analogies that only dancers will understand