One of the oldest and most effective ways of quickly finding other researchers with the same interests is to use the Rootsweb Surname List (RSL).
From the Rootsweb home page (http://rootsweb.ancestry.com/) the Rootsweb Surname List is the first link under the Search Engines and Databases set in the left-hand column:
Clicking on the link for Rootsweb Surname List/RSL takes you to http://rsl.rootsweb.ancestry.com/ :
On this page, you can enter a surname into the search box (I entered "seaver" in the screen above) and click on "Submit" button, which brought up this screen:
There are a number of entries on the RSL for "Seaver" surname - the table above has columns for Surname, From, To, Migration, Submitter and Comments. My entry is the top one - I entered Seaver from 1608 to now, migrating from England to Roxbury MA, USA to Westminster, MA, USA. My Rootsweb user name is in the Submitter column.
There are 16 entries for the Seaver surname, and not all of them have entries from colonial Massachusetts. But several do. Perhaps they are cousins. Do they know more about this surname than I do?
How can I find out who they are and what other surnames they are searching for? If I click on the username (I chose my own), then I can see the information that person:
My name, current email address, the email address I used when I first added my names to the RSL, and my home address are shown. Not everybody adds all of that information, of course, or has kept their email address up-to-date, but it's a lead.
There are several pages of entries for all of the surnames that I entered into the system back in about 1998. I have a few more to add now, and will probably do that in the next week or so. How do I do that? There is a link at the bottom of the screen above for "Add your surnames to the RSL."