Fossilized dinosaur eggs ar really found in the US. Fragments of Lambeosaurus eggs have been unearthed in the Montana Judith river formation. Most discoveries are fragmentary. This one has a very nice size and shows really good details of the shell structure.

Lambeosaurus paucidens

Late Cretaceous (70 -66 mil.-y)

Judith River Formation, Montana, USA

15 cm - 6" (egg shell section)

Very good