UPDATE: Please read Other Market Apps on your Android Phone for a work around which really works.
Okay so to make it available again, follow the below mentioned steps:
STEP ONE: visit http://www.appbrain.com/ and use your Google ID and username to sign in with Appbrain.
STEP TWO: Go to Android Market and Download and install ‘Appbrain App Market’ and ‘Fast Web Installer’.
STEP THREE: After installation of Appbrain open it up and sign in with your credentials. Go to "Manage my apps" and click the "Sync with AppBrain" button.
STEP FOUR: Go to Phone Settings > Applications >Manage Applications and Click on Market
STEP SEVEN: Open AppBrain App and go to preferences and Select Enable Fast Web Install
Please leave comments if this worked for you, also add your cell model and Android Platform info. This will really help others who read this! Thanks!
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