Booking in advance is recommended, trains can sell out weeks in advance. I have a feeling it might be one of the first things I do when I get there, though there IS a quota for tourists so they can buy tickets closer to dates of travel. I've done about 3 hours of research tonight, and I believe the train from New Delhi will be about $54USD for 1st Class Air Conditioned. After scouring Lonely Planet, I've figured out that an Upper Berth is preferred if you want to stretch out to sleep.

Otherwise, looks like the train ride is about 11 hours. I've found one that gets me in around 9am, seems safest. The other all arrive at about 4am. From what I've read so far, it's best not to be out b y yourself as a western woman after about 9pm.

The trains site alone took about 1.5 hours to decipher. I've found hotel sites that don't list prices... all sorts of odd things, but this is the oddest to date. This is just one screenshot of classification codes for discounts on the rail system. There wa a whole section of discounts for circus workers, and my favourite, FREE fare to unemployed youth going to a job interview.