There are 2 websites of Income Tax Department
www.incometaxindia.gov.in (To Learn income Tax Act and Rules)
and
www.incometaxindiaefiling.gov.in (For Efiling Income Tax Return)
How to Download ITR
Go to www.incometaxindiaefiling.gov.in
Click Downloads
Click ITR Form
Select Assessment Year
Download Form
You can download in either
Excel Format
or
Java Format
It will be downloaded in Zip format
You have to extract first and then use it
After filling it,we have to Generate xml
This xml we have to upload at
www.incometaxindiaefiling.gov.in after login