No. They're not listed here that way. (There are lots and lots of threads on that question. See, for instance, http://www.trulia.com/voices/Using_Trulia/can_trulia_help_me
Yes. Some of the homes listed here for sale are possible rent-to-own homes. Similarly, some of the rentals are. But you (or your agent) have to make it happen. You have to make that proposal to the seller or the landlord.
Here's a link to a blog I wrote on how to find rent-to-own properties: http://bit.ly/findaleaseoption
Hope that helps.