A good site for finding tattoo ideas, as well as tattoo artists in a specific area is Tattoo.com. Sites like TattooFinder, Facebook, DeviantArt and Pinterest are also good options for finding tattoo designs and ideas.
Facebook can be a good resource for tattoo ideas, as there are a number of artists and tattoo enthusiasts, as well as professional sites like Tattoo.com who regularly post tattoo images on their Facebook pages. Alternatively, TattooFinder.com has a large database of stencils and images for designing the perfect tattoo.
If one is looking for a tattoo related to a particular idea or phrase, searching images on a site like DeviantArt.com is an option that offers many ideas, as well as the option to commission customized artwork for the tattoo.