E.D.
You should NOT pay for a Talent Agency. That's the first sign that they are NOT legitimate. There are LOADS of people out there willing to sell you dreams for a lot of money with nothing in return. Especially parents who are unfamiliar with how the business works.
There is a book you can buy called The Kids Book: A Guide to Acting in Chicago. (The library should carry it.) Go to www.performink.com to order. You can also go to Act One www.actone.com and buy the Act One report which lists all the local agencies and whether or not they have a children's division.
You do NOT need professional pictures for children. A great color snapshot will do. Don't let them convince you otherwise. Kids change way too quickly to drop $###-###-#### a year on professional pictures. But a great color snapshot (that shows personality as well as looks) will help you get seen by the agencies.
And lastly, think seriously about whether or not YOU want to do this. It will be your job to take her around to all of these auditions, to deal with the agencies and casting directors. There is often very little notice before an audition, it's usually some place downtown, and for some you can wait around for 2 hours in order to be seen for 5 minutes. With acting and modeling 5% is the actual working the job of it and 95% is spent trying to get those jobs.
If your daughter is patient, flexible, agreeable, and has an out going personality, and you have the time to devote to this then give it a go. Chicago is a great town for it.
Good luck!