Is this a web page that already exists that you didn't create. If so, then you will have to write code that parses the HTML and get the data you would like.
Or you can create your own Servlet, that your MIDlet calls, in which the Servlet does the call to the outside Web Page, and parses it on behalf of the MIDlet, and just send back the needed text to the MIDlet.
Otherwise, I would suggest creating a seperate Servlet for you to call that will only pass back the specific text that you want. Or if you don't have Servlets, then create a new "html" page that will just be text that sends back the information that you want.