Decide whether you want your tattoo in black and gray, or full color. Any design or image you find can be altered, or the colors can be changed, use your imagination. Do a global search on Internet, the more specific you know the style you are looking for, the better return you will get. Be prepared searching for the particular tattoo design style you have in mind, don't get swamped by the overwhelming returns.
Tribal tattoos have been practiced for thousands of years. Modern people still get them done for many reasons such as to belong to a modern 'tribe' even if they do it on a subconscious level. Getting tattooed was also seen as a rite of passage into adulthood.
Considerations you should keep in mind when choose your tattoo style. Possibly the best source of inspiration when looking for a tattoo is tattoo magazines, they often contain full-color photos of truly first-class tattoos. Look for designs in magazines, books, posters, stickers, and everything else you can come across.