Getting There

From Calcutta starting in the wee hours of the morning (6:00 am is really early for most Bengalis), you have trains coming to Durgapur at regular intervals. Frequency slows down a bit in the afternoon though. So at 6:05 am you have the Shatabdi Express that takes you non-stop to Durgapur in about 1hr and 45 mins. At 6:10 you have Black Diamond Express: takes 3 hours (because it travels on the main line). After that, you have a bunch of long distance trains that stop at Durgapur: you may have to pay a higher price for the tickets. In the afternoons you have Mayurakshi Fast passenger leaving at 4:30 pm (not recommended unless you are a cheap bloke. The daily passengers there will make your life hell). Right on its heels Coalfield Express, Asansol Express, Kalka Mail.....
By Road, if you are coming from the Central or Southern part of Calcutta (Chowringhee and south), use the Vidyasagar Setu to cross over to Howrah and keep going till you hit Bombay road. Turn right and stay on Bombay Road to reach Delhi Road (NH2). Take NH2 towards Durgapur (also known as Durgapur Expressway). I drove mostly at 120 Km/hr, with two stops (should not need them), you should be home in about 1:45 mins.
From North Calcutta, currently you will have to take the Bally Bridge (Dunlop,Dakshineswar etc.) and continue on to Kona where you hit Durgapur Expressway.

From North Bengal (Siliguri, Malda etc) You can avail one of the nany trains that go to Sealdah. Get down at Burdwan and you will have to change trains to get back to Durgapur. It is about 45-50 mins train ride from Burdwan to Durgapur. I have also heard of a train that goes through Durgapur to Asansol and then turns North. Not sure what it is though.
The Best bet is by road. Catch the Rocket(yes thats what they call it there!!!) bus to Durgapur. Stops at a couple of places. Comfortable journey if you are not sitting in the back seat.

From West (Delhi,Patna etc): With low cost carriers like Air Deccan, Spice Jet etc., you might wanna fly in to Calcutta from Delhi and then either drive or ride a train to Durgapur. However, my personal preference is to ride the Sealdah Rajdhani Express from New Delhi to Durgapur. Very comfortable journey. Get up in the evening in Delhi and after a nice nap at night, you are at Durgapur at 7 am. Otherwise, there are a mutitude of trains: Poorva Exp, Kalka Mail, Toofan(don't unless you have to) etc.