Check out the vendors on the forum, banners at the top (including the one mentioned) and listed in the classifieds section. You'll get lots of ideas, and the toys you can be sure are chin safe and the prices tend to be a lot cheaper then at pet stores.
Basically though the best toys are chin safe wood. Cardboard is ok so long as your chin doesn't eat it, chewing it is fine, but if swallowed can cause a gut blockage problem.