Swampworks is out of business. At least for combat warships. They will no longer be producing hulls.

http://floatingdrydock.com/
Just scroll down to plans. Click on the link

What you're looking for is ships of the same class. Use your Conways or Janes reference books to identify ship numbers of the same class as the USS Hammann, DE-131. In this case we find that floating drydock lists the
TFW-DE133/4 USS PILLSBURY DE133 a close sister ship referanced by ship numbers.
http://floatingdrydock.com/TFW2.htm#TFW
scroll down from the large ships Battleships=>Aircraft carriers=>Cruisers=>Destroyers/Escorts
. . The Hammann is a DE, so continue scrolling down through the list of TFW-DD=>TFW-DE.
There you can check the plan numbers and ship names for DE's where the
TFW-DE133/4 USS PILLSBURY DE133 is listed.
Choose the scale of plan you want. I typically choose 1/72nd scale, or the smaller cheaper scale, then rescale the areas of the plans I need for cutting templates. The rest of the plans I just factor enlargemnts or reductions as I build.

Once you have the plan number and description copied then, At the bottom of the page you can click for an order form or online ordering.

[8D]