No, they don't. They won't even sell it anymore, since 2009 or so. eBay and other used markets can be used to get 10.5, but it is still very expensive (approx. 100 USD and more), when you want a RETAIl version and not the grey RESTORE DVDs, which you can get via Apple anyway and they won't work on any other model than the one they came with.
If you have an Intel Mac, you can always get Mac OS X 10.6 Snow Leopard for 29 USD here.