It is possible to search the Rootsweb Mailing List Archives for the DeHaven surname.

To subscribe to DeHaven Rootsweb Mailing List, click here: DEHAVEN-L

It is also possible to find messages on the DeHavens and related families in the online archives for the mailing list Original 13 Settlers of Germantown, Pennsylvania

There's an online bulletin board for the DeHaven surname at Genforum.