Well, I think .. in fact it is the Colophon of the site.
So why not create a colophon page, that can be linked to the "site made by ..." link which is often at the bottom of the (home) page?
Instead of directly pointing to the site of the webmaker, it can go to the colophon page: were (among others) the link to the webmaker's company can be included, and of the photographer(s), copywriters, etc.
Better for SEO and PR (public relations in this case) too!
Such a colophon page can be as simple as the txt-file above, but then as html-file so links can be clicked; it can get more attention if it's in the design of the site.
And you can make it as attractive as you want.
*) Dutch title means: "Sparks for a fire".
Oops, example was made some years ago, working in FF and IE7 at that time; doesn't work in Chrome now...