Been on Connie, and yes you can eat in the Windjammer in the everning, they set it up just like the main dinning room, and they have 3-4 styles of food, you don't have to book, but you can and it may be best if you do. Its a great place to eat. They also have bookable payable restaurants.
There is no buffet called Windjammer on Celebrity - you are getting confused with RCI. The buffet area on Connie is called Seaside Cafe/Grill. The casual dining area has a gratuity of $2, it is set up with table cloths and linen napkins and has the same menu every night, and it always has one of the entrees from that nights main dining room selection. I can post the menu if you wish. This is where they are training the waiters for the main dining room. As stated before there is no buffet.
Would you be able to post menu by email? I am also on Connie in July 09?
Celebrity have fixed dining times of 6 and 8.30. There is no buffet as such in the evening on any Celebrity ships. You can book the Alterntive casual dining for $2pp, or you can book the speciality dining for $30pp, or you can eat sushi and have freshly made pasta or asian stir fry in the casual dining area.