Website change detection software

Hello. I want a program that constantly monitors websites and send me an alert when a specific page on a website changes in certain ways (usually simply when information is added). Here are some example programs that this would be like: [login to view URL] [login to view URL]~markwell/webmon/ However, I would want the program to be quicker (refresh the webpage every 30 seconds), cover more websites (eventually around 1,000), and be more intelligent ## Deliverables I need a programmer to write a script. From what I understand, this might be somewhat simple to make, Google monitors websites non-stop with their spiders. There are different kinds of monitoring and alerts that I would like to see: 1. The simple kind is if the website changes at all. 2. More complicated, for some websites I'd like to only be alerted when certain key words pop up on a particular page. 3. For other websites, I'd like for the program to have some intelligence. For example, when a keyword comes up on a website, I want the program to click that link, and then look for more keywords, and if they're there, then click on the next link, and at this point search for keywords again. If the keywords show up, only then do I want an alert. (Note: we can start with the simple kind and then get more complex as the program is developed) I need to be able to change the different sites monitored and key words on a regular basis. Although I'm sure adjustments will be needed and the program will be constantly improved as I use it, the end result should be a program that can used and adjusted by me without having to call a programmer all the time. I also expect to do several beta tests done before the final product is complete. The way this would work, is a web based server would analyze the webpages and send the alerts to me on my desktop program. I've heard some servers only charge $15/mo, if you know of a good one please let me know. I'd like somewhere between 50-1000 webpages monitored at all times, if possible. We'll start off small, with only about 20 pages monitored, but I plan to keep adding webpages until I reach about 1000. They should be refreshed every 30 seconds or one minute. When the alerts come up, I'd like them to come up on a table, with the website, keyword, and time of the alert. Also, I want to be able to rank each alert for importance. If you think you can make a program like this, please let me know. Speed is essential, I want to know about the website change ASAP. I also could use advice on how the program could best be used, created, and maintained. I'm very passionate about this project and it will be long term. I would like to be able to talk to you via Skype. Please feel free to ask questions.