fae:

Wal-mart has the popular childrens themes and you could sew two twin spreads together for the large size problem, use the extra material on the length for pillow shams! Bind off the cut edge with pilling from the sewing department in the color of the spread. Good luck!

fairy kisses:

Domestications.com is a great place for the cute girl stuff and I believe they offer most in twin and Full.

donna d:

overstock.com