hi Heather,
I will advise you to not to miss Rajasthan(which has famous cities like Jaipur, Udaipur, Ajmer, Pushkar, Jodhpur, Bikaner, Jaisalmer which have lovely palaces and forts) . Also the places in North india which are not to be missed are Agra(Taj Mahal), Varanasi, Delhi and if u like the hills then head straight to Himachal pradesh which has beuatiful hill stations like shimla, Manali, solang valley, Dharamshala, Mc Leodganj. If ur visiting India during july-October and are of the more adventurous i would advise u not to miss Leh-Laddakh and its surroundings.
The road journey from manali to leh of 470km, passing through spectacular landscape is worth the pain. Moreover Himachal Government tourism runs a daily bus service from manali to leh with an overnight halt in a tent in a beautiful valley called Keylong. The bus has more foreigners than Indians. Once u reach Leh u have 2 important excursions..one to Nubra Valley and other to Pangong Lake. The road to Nubra valley passes through Khardung-La, the highest motorable road in the road at almost 6000metres. Pangong lake at an altitude of 4200m is a beautiful lake which is 120Kms long, half of which is in India and the rest in China. Apart from these there are numerous trekks available ranging from 4 days to a month.
Once north india is finished u can move to Mumbai(which has elephanta caves) and visit Goa which is an overnight journey from mumbai. Goa is famous for the beaches and typical Goan cuisine.
Then moving on to South india, which is famous for the beautiful temples,places not to be missed are Madurai, Mysore, Chennai, Tanjore, Hampi. What i recommend the most is to visit the State of KERALA, which is called the God's own country. This state has a number of backwater cruises to suit every budget. In Kerala, the traingle of Munnar(hill station), Thekkady(wild life reserve) and Alleppy(Centre of backwater activites) are not to be missed.
Though i have not detailed Eastern and Central India if u have time, u can explore these also.
Regarding internal transportation, where long distances are to be covered, it would be preferable to take the ariel route. Various low cost airlines have come up during the past few years. Some of these are:
www.airdeccan.net
www.goair.in
www.goindigo.in
www.flykingfisher.com
U can prefer train/bus for shorter distances. Train tickets can also be booked upto 60 days in advance at www.irctc.co.in
Regarding accommodation, India has a host of options from budget to expensive ones and the rate depends on the season when ur visiting.
Kingfisher beer is the local and widely popular brand in india which is available cheaply. I am in mumbai, if u happen to be in mumbai, i will throw a beer party for u
Do let me know if u need more
I would be more than happy if u come to India, enjoy and leave back refreshed carrying fond memories of India
Cheers
Arif