1seo: If I have an all graphical page, where can I place keyword phrases for the search engines?

Try to install a SEO plugin where you can insert your keywords.
Also, you can make a section for the site (not visible on the first page) where to write some articles related to your business/keywords.

Definitely make great use of your META tags in this situation.
You could also include some header/footer links to some onsite content or a blog.

This would greatly negate the difficulties of the scenario.
Best of luck!