My wife is a published writer. She has 4 books out right now.
1 self published
3 published with two seperate publishers

She has been published for over a year now and sells over a 1,000 a month with all combined sales.
She has been the book of the month for top romance websites and has been nominated for the book of the year for her category.

She was a lawyer for 5 years, top of her class and all that shit. So she is sharp and will continue to write... NO! I haven't read any of them... I will take the word of the romance critics and I don't read roamance... I tried... just can't do it.

Anyway sales are increasing by 40% to 50% every month on Amazon and Smashwords but I want more.

Any ideas? No I'm not telling you thieving bastards what her pen name is or the book names. ;-) Nothing personal but I'm sure some of ya'll already sell bootleg ebooks. lol

Her ranking on Amazon has jumped from 60K to 15K and keeps climbing.

But there must be something ... I'm thinking of adwords but so sure.
I figure adwords is cheap for her key words and with a $3 price point the conversion rate should be high.

To increase profit you may also
1) sell via Clickbank
2) become viral on facebook

Maybe you could also ask blog owners / communities to review her books and place a link to her site. Word of mouth works like a charm in this niche. My friend is a huge PNR novel reader and also runs a blog (german language) about romance novels where she reviews them and stuff. I guess she'd love to get her hands on some not yet so well known authors books (on the other hand, maybe she knows your wife's books already - who knows lol). Let me know in case you're interested