Start Learning Javascript (Online Tools, Blogs and many more)

This article is for those people, who have recently developed interest in web programming. Hope you have learned server side basics and now you are trying to impress your friends with nice User Interface of your website. When you will start doing the client side web development, the most annoying and frustrating thing you will find is 'BROWSER'!!!. DOM parsing APIs varies from one browser to other and that result in error and frustration.
NO PROBLEM. We have YUI (Yahoo User Interface). It’s a JavaScript library form Yahoo. YUI.DOM APIs exposes some set DOM parsing APIs; they manage the cross browser problems centrally. So that we web developer can have easy time concentrating on feature rather than dealing with browser complexities.
YUI also provide CSS files that helps in getting a uniform look across the browsers. Request you to read in details on YUI site. They also have some videos on their site (YUI Theatre),

Tools
Editor: My recommendation for javascript editor will be Notepad++ OR Aptana Studio .

Debugger: Now Once you are ready with your code, where will you run JavaScript??? of course you will test in browser. But we have best browser to test!! Its Mozilla Firefox. Make sure that you have FireBug (a add-on for firefox). If you don't have you can download it here
I love firebug, this is the best debugger for JavaScript.

Beautify: Now sometime you will love to beautify your JavaScript code. Just to have better control and readability. Though most of the editors do it, but here is an online tool to do it. It’s called Javascript beautifier.

Static Analysis: Now finally here is another JavaScript on-line tool to verify and find some critical problems in your JavaScript code!! JLINT

Tutorials
This is one of the nice tutorials about JavaScript. Here Do not forget to go thru the videos on YUI theater. specialy this one
Yahoo! JavaScript Architect Douglas Crockford provides a comprehensive introduction to the JavaScript Programming Language in this four-part video:
Part 1: 31 minutes
Part 2: 31 minutes 
Part 3: 29 minutes
Part 4: 20 minutes
Download slides (zipped PowerPoint file)
Blogs
I will love to recommend these 3 blogs.
http://24ways.org/
http://www.yuiblog.com/
http://ajaxian.com/
I love to recommend Christians personal blog.. He is a geek so you can track his blog as well.
http://www.wait-till-i.com/

Do not forget to see this JavaScript library. if you are looking to have some cool animation on your site.
http://script.aculo.us/

That’s it enjoy developing and Mashing Up.. Ooh ya here is few nice things to do mash up
YQL and Google ajax playground