Well I came across it after reading an article on the mobiletuts+
Previously, whenever I read about people (especially young 14 year olds) creating iPhone Apps, those people keep saying that it took them like two weeks to learn how to create an iPhone app, and that it takes them a few days to create the app, and if they needed to add a stage to a game that they made for the iPhone, it will only take them a weekend!
I got intrigued, and decided to use my Apple hardware (including a Mac and two iPhones) to start creating my own apps.
The obvious way was to use Apple's XCode.
But as I went down that road, it became kind of obvious that it will take me monthes to learn how to write an app, and it will take a much longer time to build an application!
I felt both jealous and frustrated! how can 14 year olds do it in a few days, and an electronics engineer like my self can not!
So I kept digging for resources, and when I came across the Corona SDK, it all became clear to me!
You build your apps using a scripting language called Lua (which is a scripting language that is much easier to learn and use than Apple's Objective C).
I was shocked to know that some of the top selling applications for iPhone and Android were built using the Corona SDK!
Take for example the famous Fruit Ninja game, it was actually a template on the Corona SDK site, and it only took Half Brick studios 14 hours to build it!!
I can tell you, this SDK made me so obsessed with building my own applications!
Now, even though the Corona SDK is easy to learn, you still need a reliable source of tutorials and documents to take your hand through the learning process.
No place is better than Techority.com
( UPDATE [13-JAN-2013]:
The owner of Techority.com, Peach Pellen, left Corona Labs, and thus she removed all the Corona SDK tutorials. She is not providing any support to Corona users.
So For now, we recommend LearningCorona.com , as an alternative, till we right some more reviews).
It is even recommended by the Corona SDK people!
The web site is run by an Australian lady who goes by the name "Peach Pellen".
She has an amazing tutorial for newbies, that helped me real good to get into the game! a well prepared introduction indeed.
She also has a number of other useful tutorials for basic and advanced topics of the Corona SDK.
And she is even offering her services as a private tutor!
Techority.com is a must if you want to start learning Lua, and the Corona SDK.
I urge you to Check it out!