Accessing web page information

I am trying to obtain some strings and number values from a web page that was made with Javascript. I thought of accessing the web page directly or getting the info from the source file. I tried using StreamReader but it doesn't accept URLs. I saw a ton of other Web file related classes in VS help, but no information on them. It would be very helpful if someone could instruct me on some classes to use or point me to a resource. Thanks in advance.