How many Aiel clans followed Rand into the Wetlands? How many Aiel follow Rand as of TSR? Did more Aiel come to follow him in later books?

At first Rand had 7 clans under his command, when he entered the Westlands in TFOH, then 4 more joined after he beat the Shaido in the Cairhien battle.

Technically Rand was followed out of the Waste by all clans save the Shaido whom Rand followed.

Once his identity and prowess as Car'a'carn are confirmed, Rand leads every clan except the Shaido and the Brotherless.