Getting text from a URL in ASP.NET

I am looking for a reliable way of extracting text given the web address, in ASP.NET/C#. Can anyone point me the right direction?

Also, the web address could be say a news site that might have a lot of ads and menus etc. I need some intelligent way of extracting only the relevant content. Not sure how this could be done as how would I define what relevance is?

Should I maybe read from a RSS feed? Any thoughts on this?

EDIT I Have added a bounty. I am looking to extract "relevant" text from a URL. From "relevant" I mean, it should exclude text from ads (and other irrelevant info). The input will be similar to a news site. I need to extract only the news info and get rid of the extraneous text