First up - there's no accommodation next to T2 - so intl. pax need to catch a taxi for sure. Only T1C (domestic) pax can walk across the road to the smartly named "airport hotel" which is decent but a bit costly.

If you have a budget of 500 INR:

Call up International Youth hostel Chanakyapuri - they have non-AC dorms for 150, AC dorms for 350(you need your lock). They have rooms as well.

If you have a budget of ~1000-1500 INR:

There are multiple hotels around Mahipalpur(http://www.asklaila.com or justdial.com) are your friends. Pay 1200-1500 for AC room, and 1000 for nonAC. There's Paradise 011-26784047, Tarra 011-26783677, Swapnil 011-26782508 among others.

Catching the cheap (you get what you pay for, do haggle for an esteem) black/yellow cabs to the IYH may be the simplest solution for some.