I'm never afraid to parrot good content, so allow me to create an easy-to-find place marker for the CDC immunization price list, care of a reminder from Susanne Madden. Here's a sample of the data:

Although the "Private Sector Cost/Dose" is of dubious value, it's at least a start (in other words, if you are consistently paying more than this figure, time to check out one of the immunization buying groups). I also find it useful because I can never remember which brandname goes with which vaccine, I always get them wrong.
Oh, you can find this chart here.