Titer Test

For a human? Just ask your primary care physician. I had to have one done for measles last year, it was about $100 - be careful, my insurance did not cover it and I had to pay for it out of pocket (it wasn't for health reasons, I needed it for work).

For a human, have your doctor send you for blood work. Any lab can draw the blood and send it for this test. Most insurance's will not cover it though so you may have to pay out of pocket.
For animals, talk to your vet.

Isn't it just done through normal bloodwork at a lab or are talking about different kind of titers?

I don't know about Portland, but the local lab that does the normal bloodwork drew and tested mine.

We got an antibody titer test for our daughter at Qwest Diagnostics, different locations in Portland and Beaverton. Your pediatrician will probably tell you where to go, but we had to pay out of pocket since the tests were elective (to help us decide if she needed more particular vaccinations).

You mean for vaccinations/etc.? Our vet used to do that for our dog...I would say anywhere that does bloodwork...