i am starting to study FLEX. i have only flex sdk. So can i start study only using that. If so please suggest me the link to go through..
But still, Using an editor
Flex Builder (now Flash Builder) is based on the Eclipse IDE - it's actually a plugin to Eclipse. So with Eclipse being open source and free, you can use that as your editor.
You won't get the integrated debugger, and visual design view... but using some free plugins you can still be productive.
1) You'll need the Flex SDK: www.adobe.com/products/flex/flexdownloads/
2) Get Eclipse: eclipse.org/
3) Two notable Eclipse plugins: - www.eclipse.org/webtools/ - www.aptana.com/studio
Alternatively, if you have MSFT's Visual Studio, there's a Flex plugin for that too: - www.sapphiresteel.com/Adobe-Flex-Development-in-Visual
To compile your code you'll use the Flex compiler, information on how to use it can be found here:
www.adobe.com/livedocs/flex/3/html/compilers_13.html#150640
Chapter 2 of Flex 3 In Action also has a section on how to develop Flex applications without Flex Builder:
http://www.amazon.com/dp/1933988746/?tag=insidemark-20
Note that Flex Builder is free for academic faculty, students, and out of work coders. So that's another option.
Cheers.