Did the Dutch have Germanic gods that they worshiped?
I'm much more familiar with the Christianization of Germanic peoples, but this is what I've got:
The Dutch are more-or-less the cultural descendants of the Franks. Please note, I am referring to the Dutch specifically inasmuch as they can be defined as a people, not to other peoples whose territory now comprises part of the Netherlands, like the Frisians, etc. Like all Germanic mythology (only moreso), Frankish mythology is not well-defined in the sources that have come down to us, but it is generally agreed that they adhered to a modified version of the classical Germanic pantheistic religion. There is evidence of the worship of Odin (called Wuotan), Freia, Thor (Donar), Tyr (Zio), and Freyr (Yngvi), and some have argued for the worship of Nerthus by the Franks. If I understand correctly, however, gods tended to be worshiped locally, with little overlap from region to region. I am not sure what impact this had on the cohesiveness of the pantheon as we usually think of it. Present were also the other characteristics usually associated with Germanic paganism, such as the consecration of natural spaces and the belief in the physical existence of their gods within the world. There are a few scholars who try to make further differentiations between classical Germanic and Frankish mythology, but, because we have so little information, none of their assertions can really be proven one way or the other.
In terms of sources, you might be interested in the following: