Where can you get your vaccination immunization card?

From the doctor, when they give you a vaccine.

eg. When I got my Q-fever vaccination, I needed to get 'serology' done first, where someone checked my blood sample to see if I already had antibodies to Q-fever. When it was confirmed that I didn't, I had to get the vaccine, and the doctor printed a certificate as 'proof' that I had been vaccinated. If my serology had shown that I DID have antibodies before vaccination (ie. I had already been exposed to the virus and had naturally produced them), I would not have had the vaccine (it would have been detrimental - that's why the serology check was important, and the skin-prick test with a SMALL bit of the vaccine to see if I reacted to it). If my serology showed positive, I would have been given a certificate to say that I did NOT need the vaccine and already had antibodies.

Reason for doing all of this: employers can be liable if you get Q-fever and end up lethargic for months, recurrent, for the rest of your life. It is therefore their responsibility to ensure you have appropriate protection against work hazards - eg. if you end up working with sheep/cattle/etc. I paid for my own (it was expensive), but if you are working in a high-Q-fever-risk-job, you can often ask your employer to pay it for you, or you can claim it back on tax (the second option is less preferable if you are beneath the tax-paying threshold and you claim all of your tax back regardless)