fetching data from a different website's database

I have a specific website that you could search for specific data - like if you put in a name and address it will give you more info about that person.

Now, I'm interested in a specific type of result - for example - I want that site to give me every person that lives in this and that neighborhood and is between 30 and 40 years old etc etc... (that site doesn't give me the option to search for any keyword of any sort - just a specific name one at a time..)

Is it possible to create such a programm with absolutely no access to the code?

If yes, What would it take to acheive it?

I appreciate your response!

Thank you!!