There was the Kingfisher, Warlord, Cerberus, Phantom and Revenant that came along with the Ship of the Line. They were - and are - meant to give us "Special" broadsides like Firebrand and Thunderbolt, which was something that was of much talk on the Forums a while back.
The Kingfisher120,000 Gold
The Warlord was 180,000 Gold
The Cerberus was 140,000 Gold
The Phantom was 170,000 Gold
The Revenant was 190,000 Gold
There are videos out there showing the ships back then.
http://www.youtube.com/watch?v=pzl6dqoDryQ shows the ships at a Shipwright's "Purchase" section.
The only known ship that was purchased was the
http://i1236.photobucket.com/albums/...ingfisher1.jpg
...which had Chainshot Broadsides, 1,200 HP - yes, half a Light Sloop's HP - space for 14 cargo like any War Sloop, and room for 3 players (as if crew capacity really matters anymore these days).
http://i1236.photobucket.com/albums/...ingfisher4.jpg
Really, aside from the Chainshot broadsides being horribly pathetic, and the Hull being dreadfully weak, it's not that bad to sail a Kingfisher.
This video,
http://www.youtube.com/watch?v=cbgjLEyTdz8 shows the Kingfisher itself.
Lotsa links, yes indeed. Go view them!