where can i find a queen size tweety comforter.

The biggest size I found was a full size!  That still will fit though, just will not go as close to the floor, you would just need a coordinating bedskirt!  You can get a full sized comforther for $49.99
specifics
Tweety Bedding continues to be a favorite among kids, whether they're a boy or girl. You can decorate their room with the Tweety and Sylvester playful pillow fight bedding.   The Twin size sheet set includes 1 pillowcase, a flat sheet, and a fitted sheet. The Full size sheet set includes 2 pillowcases, a flat sheet and a fitted sheet.  You can also buy a more pillowcases separately. After all, do kids really ever feel they have enough pillows?

• Sheets and Drapes: 60% Cotton 40% Polyester 
• Comforter: 55% Polyester 45% Cotton
• Machine Wash cold with like colors & non-chlorine bleach/tumble dry low – remove promptly
• Imported

Children always feel better about bedtime when they can fall asleep surrounded by their favorite cartoon characters or heroes. Tweety Bedding gives them that opportunity night after night. The Tweety Comforters give them the opportunity to drag their favorite "blanky" throughout the house, wherever warmth, comfort and a sense of belonging is desired. Tweety Tweet Dreams Bedding is a complete collection of Tweety Bedding. We also offer Tweety comforters, Tweety sheets, matching pillowcases and window treatments. The warm and cozy Tweety comforters are made with a fun and playful pillow fight design. The top of these Tweety Comforters features a big graphic image of Tweety on a purple background with the image of white/purple feathers falling to the bottom. The reverse of these Tweety comforters is small images of Tweety on white ground. Tweety Tweet Dreams Bedding, available in twin or full, also features an adorable sheet set, which features the same Tweety pattern on white ground as the bottom of the comforter. The sizes of the full sheet sets are as follows; flat sheet (81" X 96") and fitted sheet (54" X 75") with 2 pillowcases.The sizes of the twin sheet sets are as follows twin flat (66" X 96") and fitted sheet (39" X 75") and 1 matching pillowcase. Tweety Tweet Dreams Bedding will help your children dreaming of pillow fighting with Sylvester and Tweety. One side of the pillowcase is light purple with the same falling feathers as the comforter and a dark purple background while the reverse side features Sylvester on an light purple/white polka dot ground with a dark purple border. Completing their Tweety Bedding is a coordinating Tweety Tweet Dreams window treatment, which consists of a 41" X 63" 2-panel set and matching tiebacks. The panels are light purple with a dark purple wide stripe, filled with Tweety designs, ¾ of the way down and a narrow white stripe below. Overall, a fun and playful pattern.