As the boat tossed to and fro, my tummy tossed like a...

Well, I don't give google links but I personally read old Classics to get a feel. They had much better descriptions back then.

moby Dick was early 1700's and all the others I read were later and in the 1800's

But that's what I do.

Ships 1697?

Cargo ships were called Merchant ships because they usually belonged to Merchants trading as companies or families.
They also tended to go not on the high seas but on courses nearer coastlines so they didn't get lost. Remember no longitude to work from back then! Getting from place to place meant sticking to traditional routes and sighting points.
Where are they sailing from? You need to get the correct route.
Information on ships can be found at the British National Maritime museum at Greenwich. As I can't find my reference source you'll have to google it.

As Rtilryarms says reading novels written in the period could help. But there's not much available. Ships changed radically between the mid 1600s and the mid 1700s so don't fall for details of a mid 1700s ship.

Some other useful sites would be:
http://www.bloomsbury.com/ARC/Arc_home.asp
Bloomsbury publishers have a reference section online using their books. You might find something there.
http://www.pikle.demon.co.uk/diaryjunction.html
Is a collection of original diaries online. There is one I know of a 17thC sailor who writes his diary on the ship.
http://www.history.ac.uk/
This is the serious British research centre. Takes a while to get round it.

Connecticut to London?

Could be dangerous. Pick the right time of the year as that Atlantic route was fierce at times in the autumn, winter and spring with storms. These little ships had to dodge storms, so often were delayed.

The Navigation Act of 1696 required that all trading with the Colonies had to be done in English built ships.

So you'll want to be sure to have your characters aboard an English made ship!