I have started learning Flex programming blindly. Can anybody suggest me what things one should know before learning Flex. Detailed guidance is needed.
It really depends on your goals and background.
But in general, if for now you simply want to get at general Flex programming, don't buy a book, simply go the Flex 3 help system (here presented as a LiveDocs link for your convenience):
Even if you only go through these pages for a week and then go off on your own and start just building apps, you will have gained great insight into the major constructs present and necessary in Flex applications.
If you learn better through videos, then ToTal Training or lynda.com are good, though they don't compare to the above Flex 3 help system at all:
And if you want tutoring/training:
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