It is best not to go through sites like booking.com, taking up to 50% commission on your reservation. In addition, this site will not guarantee your reservation. Some customers have already noticed, once they got to the hotel, that their reservation didn’t exist. So you end up in a hotel that you did not booked (the hotel can be better or worse!). Send an email directly to the hotel concerned!
Here are some links to sites that can simplify your life and give you good ideas to travel:
You can also check the guide 52 breaks out of Delhi available in two versions:
Here a non exhaustive list of destinations easily reachable from Delhi!