Do you mean like this:
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As far as I can tell, that's a photo-manipulation, not done with a plug-in.
There are lots of plug-ins available. Some are free, some are not. Generally speaking, the free ones are not very good, although one major exception is Virtual Photographer
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If you don't mind paying, good plug-ins include Xenofex and Eye Candy from Alien Skin
Alien Skin Software Products and a whole host of stuff from Flaming Pear
Flaming Pear.
Redfield also do a range of good plug-ins, including the excellent Sketch Master
Photoshop Plug-ins by Redfield.
If you've got money to burn, you could go for some of the Auto FX bundles
Auto FX Software.