This has actually been discussed before:
3rd Party iWork Pages Templates???
But didn't get very far. I'm surprised you didn't find anything on Google -- I found tonnes!
iWorkCommunity: Template Exchange
(they have 292 templages for pages, quite a few in the brochures/newsletters category)
Free iwork Templates
(four nice-looking free brochure templates here)
Some free ones I found via a Ft. Langley BC website (??): http://www.itsmysite.com/cgi-bin/its...r=fortlangley2
And of course both Jumsoft
offer commercial packages of Pages Templates. This where you will find -- by far -- the most professional designs outside Apple's own.
Finally, you could just MAKE your own template -- I do this all the time, it's quite amazing what you can come up with just by using the "Shapes" drawing menu and some imagination.