I know the line of Tonks that I come from comes from Birmingham, dating back to 1600's. I have a cousin who has done extensive research, named Gary Tonks. I could connect you with him if you wish, however he does not have internet access, so back to the mail, or phone.
I am a descendant of William and Jane Tonks, who arrived in Wellington in 1842.
I know Gary has put a copy of the tree into the Wellington library NZ, but I don't know how up to date that copy is.
If you want to contact him, I know he would be happy to work with you. Just email me.