A new Beach signs set 1 found under Decor / MiscellaneousDecor, all cost 0. You need Ambitions ( or a later pack ) and to place the packages in both the "Electronic Arts / The Sims3 / Mods / Packages" directory and in the "Program Files(x86) / Electronic Arts / The Sims 3 Create a World Tool / Packages" directory for the signs to show in your game. There is an earlier post explaining how to install items in CAW.
Importing packages into CAW
Beach signs set 1
PS. These are high resolution signs giving them a superb clear image.