That's a very common, well-known scam. I went through that about a year and a half ago. It sucks that Houston Chronicle won't take steps to take those ads down. MOST of the ads on Chron are like this unfortunately. I've emailed Chron a few times reporting them, but to no avail
I always mess with those scammers and tell them to send me a picture of the pup with them holding a penny or something like that, but after I do that, they refuse to email me back or come up with some lame excuse as to why they don't think I'd be a good home for thier imaginary dog.