Indra Sinha. The Death of Mr Love takes place partly in India and partly in England, and Animal's People takes place entirely in India. But Animal's People is really not a pleasant story (it was inspired by the Bhopal disaster and is pretty brutal in spots).

Shashi Tharoor is also good. Riot: A Love Story and Show Business are the two fiction books of his that I've read. Show Business is really much, much better if you watch Hindi movies/know about the Hindi movie industry, though.

You could also try Anita Nair, who I think is really interesting because she writes mainly about South India, which I know very little about compared to what I know about North India. Ladies Coupé has some stuff about marriage and love, but it's not really what the story is about. Mistress: A Novel and The Better Man also don't really focus on marriage. I haven't read anything else by her, though.

Midnight's Children, Salman Rushdie.

easy reads: amullya malladi [i have a feeling i butchered the spelling] and samina ali.
jhumpa lahiri is always a good choice, as well, but she deals mostly with indian-american, and i don't know if that's what you want.
rushdie is godly. "the moor's last sigh" is a headspin.

"Dancing With Shiva".

Again, Rushdie. Midnight's Children is one of my favourite books, but if you want something set pre-20thC, there's The Enchantress of Florence.

Vikram Chandra - Red Earth, Pouring Rain. Set between 19thC Calcutta, and an Indian in 20thC USA.

Rohinton Mistry - A Fine Balance.

Does your icon show a girl with a tree growing out of her head, or a girl lying with her head in front of a tree? Just out of curiosity.

An excellent book that I reviewed on my journal called The Space Between Us by Thrity Umrigar. EXCELLENT. Here is the link to my review:
http://pastorbear.livejournal.com/124663.html

Anything by Jhumpa Lahiri.... Her short stories aren't always set in India but they do deal with characters of Indian heritage, often those struggling to find a place in America. The Namesake, her only novel, is also great. Much better than the movie (if you've seen that).

i enjoyed Q&A very much.

Vikram Seth is a marvelous author. ^^

Sacred Games by Vikram Chandra

Aravind Adiga's novel The White Tiger just won the Booker. I haven't read it yet, but it sounds really good.

Anything by Salman Rushie, The Namesake by Jhumpa Lahiri (although if I remember right, has arranged marriage), and it's more of a YA book that I'm not sure is still available due to controversy of plagiarism, How Opal Mehta Got Kissed, Got Wild, And Got A Life.

Shobhan Bantwal's The Dowry Bride or The Forbidden Daughter. They are both about how women struggle in india and love stories so im not sure if u would like those.

i would also recommend Chitra Banerjee Divakaruni's ''Queen Of Dreams".