hey there,
I interviewed across the nation, and can tell you the interview questions vary from school to school. For honor reasons, most schools ask that you keep the interview confidential. But their questions are easy to guess. Think clinical, personal, and ethical.
At one extreme, some schools I interviewed at were relaxing interviews where you talked about your unit, experience and them some light clinical questions.
At the other, were the interviews where they administered a critical care exam, sat you in front of a panel, and grilled you as if it were a grand jury indictment.
Either way, if you were going to "study" for the interview, i'd get the Laura Gasparis CD's and start there. Also, here is a good cheat sheet I used as a guide of which drugs to know, etc.
http://www.surgery.uthscsa.edu/saccs.../adult-mil.pdf
Then, pretend CRNA's didn't make a ton of dough, and decide if you would still want to do it. This will give you good answers to the "why CRNA" questions---even though money is a valid reason. Then, think about what ethical situations might arise if you have access to a lot of narcotics.
As far as the personal statement, I've been to law school and graduate nursing school and probally written 10+ personal statements. In my opinion, this is where you can set yourself apart from the other applicants. The trick is to get them to remember who you are from your personal statement.
For instance, you're from Chicago, probably work in a big ICU, and probably had decent grades, etc. Well, so did a ton of other applicants. So what you want to do is distinguish yourself. Emphasize your strong points in an interesting way that makes you appear competent, confident, and fun to be around. Someone on here said one time the admissions committee wanted someone who would be enjoyable to be around since they wouldspend a lot of time in the OR with them. Also, you want them to remember your personal statement. They could get as many as 500 applicants, and it will be tough to remember the guy who said "I've always wanted to be one, I work hard, and I am a smartypants."
For example, my personal statement centered around my hobby of shark fishing, and my first sentence was a quote from Captain Quinn in Jaws. I would say that at each interview about 20 minutes was spent talking about fishing for sharks. As a side note, it was very annoying when at the interview it was apparent the interviewer hadn't read my personal statement or my resume--but it gave me a reason to reconsider that's schools program.
i hope this answers some questions for you.
andy