I think 7th and 8th grade is a good time to start entering the club world. If your player is talented they will find their way onto a good team. It has been my experience that if you do your homework and make contact with the coach from your school of interest they will come to a tournament you are in and see your son or daughter play. So you don't necessarily have to be on the best or most expensive travel team to get a look......YOU NEED TO BE PROACTIVE!!!! Good Luck
Interesting points about starting with club lacrosse just before the high school years. When you think about it, so many youth players are burned out on the soccer side before high school that this approach makes a great deal of sense. The proactive comment is absolutely true whether you are talking about lacrosse or any other sport.