The next 3 links have information about modern square dancing:
1) What is Modern American square Dancing
3) 70th National Square Dance Convention Highlights
The following are links to other organizational groups:
NESRDC - New England Square and Round Dance Convention
The following link(s) are a good source for helping to learn some of the square dance calls.
(The sites have basic/mainstream/plus...and higher level calls. GOOD DANCING!)
Video Square Dance Lessons Online
TAMINATIONS (automated breakdown of square dance calls)