Hey Lalit,
If you're just studying for the exam, I'd recommend that you start by downloading Sun's free wireless toolkit. The toolkit does a great job of emulating a standard phone, and it's a great way to learn about writing MIDlets. Once you get further along you might consider a phone, but you can do a LOT with the toolkit. In fact, when we wrote the exam, all we used to
test our code was the wireless toolkit.
hth,
Bert