When you're thinking of getting a new (or your very first) tattoo, it's a good idea to research your options before you get permanently inked. You might have a general idea of what you want - like a tribal tattoo - but checking pieces others have had done will give you inspiration on your own, unique piece.
Searching the web will lead you to a ton a individual tattoo shops showcasing the work they have done, and it's a good place to start. Again, if you wanted a tribal tattoo, you'd just search Google for "tribal tattoo" and see what comes up.
If you just know you cant to get a tattoo but aren't sure yet what you want, a more general search like cool tattoos will lead you to plenty of tattooing websites and galleries that will help you find a tat that meets your needs.
It can be a tedious process, but since tattoos are for life, it's worth the research time to find a cool tattoos that you'll be happy with for life.
You also need to consider if you want your tattoo to be a copy or duplicate of something your found online, or some flash you saw at the tattoo parlor, or if you want something totally unique. Combining elements of a few tattoos to create an individual piece made just for you can be done by any reputable artist. Many will also custom design a cool tattoos based on your description.
Word to the wise - take your time in this research phase, make a decision on what you want, then sit on it for a month or so. If you still think it's the right piece for you after having time to think about it, then ge get tatted!