Can anybody tell where I can find a 64-bit version of chromedriver.exe? I tried it with 32bit also but it doesn't call the main method.
There is no separate 64-bit version of Chromedriver. The version available at http://chromedriver.chromium.org/downloads works on both 32 and 64-bit Windows, against either 32-or 64-bit Chrome.
For further assistance, please go for online Selenium tutorials.