Possible Clues:

• Org. that dropped "Lawn" from its name in 1975
• Gp. that'll teach you how to serve
• Racketeer's org.?
• Court grp.
• Org. where love means nothing?
• Org. associated with 2 Down
• Netsters' org.
• Org. for 67 Across
• Org. concerned with court proceedings?
• Org. for court pros