How much does a 1GB SD Card cost?

It depends on the size of the card and the speed.

SD (Secure Digital Flash) media cards go from 64 MB to 2 GB

There is a similar but different standard, SDHC (Secure Digital High Capacity) for cards of 4 GB and higher.

SD cards range from under $5 to over $150 depending on the capacity and speed

$30-$40