Approximately what year?

1928.. I have had no luck finding any designs online that I could replicate.

Well, 1928 is easier than 1600's would have been! For 1600's landscaping, you have to go to archeology.
To see how the Dutch Colonial revivial houses were envisioned originally, try a google image search for "dutch colonial revival houseplans" .

Honestly I've googled on more variants than I can say and have found very little

Okay, here's a suggestion. Try using Google Earth Street View and go to Shaker Heights, OH. Almost all the houses were built in the 1920's and early 30's, all are historic, and at least one out of every 8-10 houses is a Dutch Colonial. But to be honest, I don't think landscaping for a 1928 Dutch Colonial is any different than for a Georgian, a Tudor, a Colonial, etc. It has much more to do with the shape of the yard, climate, sun orientation, and owner's enthusiasm for gardening. Mostly the latter.