Most "templates" (themes) were not designed for a specific niche. They are made generalized, then you customize them with your own pictures (if you want). Much of the time, simply changing the title of the website is enough to tell people what it's about, and you don't need a bunch of moving pictures or logos!

I am sorry but I don't understand your question. What do you mean you cant find any webpage templates to match your niche? Do you mean Themes? If you are talking about Themes that is just a matter of choice as to what looks good to you. Don't worry about what pictures are on them you change those pictures when you set up your site.
I am not sure if that helped but I hope it did. If not please let me know more information and I will see if I can help.
Marc