Are you looking for your ancestors who came from the northern part of Holland? (isle of Texel) then send me an email, i could help you in your search for your ancestors.

My family tree is going back to 1700.

A relation with the Witte's from Germany, Zeeland or Texel is not proven yet. DNA tests would give an answer on this question
If you did test your DNA, and your surname is Witte, then go to
http://www.familytreedna.com/public/Texel/default.aspx
or
http://www.familytreedna.com/public/witte/default.aspx

for more info:
Peter Witte
Holland