There are two ways to reach Bhimtal, namely rail and road.
On the website, do the following:
Sign Up and fill as below:
From: Delhi (DLI)
To: Kathgodam (KGM)
under General quota or Tatkal quota, which is 24 hours before and more expensive
Specific timings for Tatkal booking when booking agents are not allowed online access is between 10 am and 12 pm (as of November 2012).
Click on Find Trains
Three daily trains, except Thursday, when the ANVT KGM SHATABDI does not run.
Cost: From a maximum of Rs. 1000/- to a minimum of Rs. 82/- (one way)
The local taxi from Kathgodam to Bhimtal costs about Rs. 600 one way.