Hi M.,
I absolutely do *not* agree with others who say cry-it-out is the only way that works. So please don't feel pressured by the typical "just let 'em cry it out" mantra that is so popular in our culture. Also, good for you that you recognize and respect your mothering instinct (to respond to your baby)! I think our current culture encourages us to go against our mothering instincts too much these days.
It's always helpful to remember that each developmental stage of each baby may require a different approach to get a good "sleep groove" going. For many babies, cry-it-out doesn't work at all or may work for a while but then needs to be redone every few weeks/months. At any rate, you have other options - there are gentle methods to help you both get more sleep.
Also, 9 months old is VERY YOUNG! Think of all the reasons why a baby might cry, (again, because this is their only means of communication!)... hunger, pee/poop/gas, teething pain, lonely, scared, cold, growth spurt/growing pains, etc. I seriously think that "manipulate my mom & dad" are NOT at the top of a 9 month old's list of reasons to cry. Many 9 month olds are of prime teething age, which can be really painful! If I were that little, didn't understand why my whole mouth, jaw, ears, and head were throbbing and aching, you bet I'd be crying at night too. AND wanting to be held, rocked by, or sleeping near a compassionate, loving parent who could comfort me. I think many adults would be really upset if they were in pain or scared in the night but their spouse just left them to cry by themselves. Also, many are 9 month olds are learning to crawl, stand, or cruise, so their bodies & brains are full of this brand new skill, causing more wakefulness.
Here is a great site that provides reasonable information on sleep (takes into account different approaches to sleep, the fact that babies have unique personalities, etc.) - I think Moxie really does better than most "sleep specialists" in terms of providing helpful information and strategies:
http://moxie.blogs.com/askmoxie/2006/06/babies_and_cio.html
http://moxie.blogs.com/askmoxie/2006/02/qa_what_are_sle.html
Many say that sleep begets more sleep, so a good, consistent bedtime ritual is a great place to start. Being able to recognize her sleepy signs is important, too, so that you can make sure she's not getting overtired (which often results in less sleep, not more, resulting in an even more exhausted baby). Many, many moms like the approach of Elizabeth Pantley's "The No Cry Sleep Solution" which allows you to create an individual sleep plan tailored to your needs and those of your child (instead of a one-size-fits-all approach, which rarely works). Another book is Kim West's "Good Night, Sleep Tight" which allows for some flexibility and more gentle strategies than the simplistic "leave them to just cry it out" method (the most extreme forms of this). Lastly, Dr. Jay Gordon (pediatrician) has written a great book called "Good Nights" in which many different families share their strategies for sleeping/cosleeping (either in the same bed, or w/ a sidecar or crib in the same room). And here are 2 articles from his website which might be helpful to you:
Changing The Sleep Pattern In The Family Bed
http://drjaygordon.com/development/ap/sleep.asp
How I Gently Transitioned My Son Into His Own Room
http://drjaygordon.com/development/ap/gentletranstition.asp
Best of luck to you - I hope you all get more sleep, and soon! :)