If i felt i had bought a supplement ( fish oil caps) that were contaminated, who or where would i take them to get tested?

Return it: Get your receipt and return it to where u bought it and exchange it with a non contaminated one.

No such resource: I believe the only resources that would do this testing would be available only if a person became very ill from the product. In general i believe you should just throw this product away or return it to the store that you purchased it at.