3D ultrasounds? Tips?

Raquel • Mom to be
We are having our first baby. I'm very excited. (My family in law don't really understand my excitement) Anyways, I'd love to have 3D ultrasound photos of my baby. Nice memory, right?
Some places are very pricey. Can you recommend me good places that won't charge me so much? Or any tips on the matter?? Thank you dears!! I live on Northwest California.