= new reply since forum marked as read
I've been to the US Open 11 times and every year since 2004. Ironically, I'm going to Montreal this year for the Rogers Cup (Men's Masters event) so I won't be going to the US Open.
Get your tickets here. Watch the dates! as ground passes (general admission, good anywhere during week 1 BUT Arthur Ashe Stadium) sell out immediately.
You're not going to like this, but...
To guarantee you see a single, specific player like Federer (or Nadal, Djokovic, Murray, Serena, and Sharapova):
1. You have to purchase an Arthur Ashe Stadium ticket (this ticket can be used to get into every stadium/court)
2. You'd bee wise to go during the first week (I only go during week 1; it guarantees I see my favorite players--none of whom I've mentioned--at least once).
3. Go on consecutive days as players alternate which days they play. For instance, Federer might play on Tuesday and Thursday. So if you purchase a ticket for Monday and Tuesday, you're golden.
4. You must purchase both a ticket for both day sessions and night sessions for those 2 days--a total of 4 tickets. For instance, Federer may play the day session on Tuesday but the night session on Thursday.
Following these guidelines, you're guaranteed seeing Federer. On the other hand, you could do a lot less and still have a decent chance of seeing Roger. If not Roger, you're guaranteed seeing at least one of the other top players mentioned.
I've never bought them off the street, but there are guys selling them. They'll find you.
PM me if you have other questions. I live for tennis 
He was ranked #1 less than 12 months ago, after all. 
My guy is Tommy Haas*, who at 35 is having a sensational resurgence. Can't wait to see what he does on faster surfaces!
*I don't need tickets to Ashe Stadium because I can see my (many) favorite players with a grounds pass, which gets you a general admission (not assigned!) seat at all venues except Ashe.
or is it just me..... I CAN NOT STAND THE SCREAMING!! and both are sooooooooooooo good at it. NOT. Ugh..... make it stop. 
