http://www.boomerangtags.com/ has stainless steel tags that last forever for 6.99 which is cheaper than the ones you can make at Petco. You can also do double sided tags on this site. I know there really aren't all that many choices, but I really like the plain ole bone.
I recently ordered 5 id tags, double sided at that, and they arrived within a week in regular mail. I highly recommend this estore for pet id tags.
They also have the other type tags; plastic, brass, etc, I just don't know anything about those from Boomerang...I ordered stainless steel.