How about that you love her unconditionally. You love her so much that you are going to make her face her problems and solve them, because one day, you will be dead and gone and she will have to do it all on her own anyway. Tell her you will always be there for her. you will drive her to rehab any time she needs a lift. You will always love her, and think she is smart, talented and beautiful. Tell her she deseves better than this, and she should use the time in jail to think clearly about the help she can get so she stops living like this. And I would put 10 bucks in her commissary (they only take money orders here) so she can get coffee or flip flops for the shower.
addicts hate themselves, so dumping on her won't help. hating her addiction is ok, just remember to love her. Keep you boundaries in place and you can always have a good cry in the car after the visit.

My son was in jail with a man who was in for rape and attempted murder with a hammer... he said "mom, he really doesn't seem so bad" and I yelled at him "NO, because you are not a woman, and he doesn't have a hammer!"
Did he really believe that, or was he just trying to make me feel better about the scum he was in there with?

How about asking her if they have aa meetings or na meetings in there, and if there are any social workers or councelors in there to talk with. Ask her where she is going to go after she gets out, and I do know amazon is allowed to mail books in directly (they open them before the inmates get them) so you could mail her a big book, or other self help book that might be helpful.

Anyway, I am so sorry, and so sad for what you have to go thru...but you are right, she must suck at stealing, so hopefully she will realize this and just stop. Stay strong. you sound good. I am very proud of how you presented your ideas to her. Good luck on the visit...I hate going into jail. and seeing my kid "under glass"

Its amazing how the addicted person always says "only" when talking about how much money they need for this or that. LOL
Let her know you love her and that you understand how hard it is to not use drugs. For most of us we cannot fathom having to have a voice in our head everyone day telling us we need to get high. If will be okay no one will know, this voice is so convincing that we believe the crap our love one is telling us while using drugs. Then we are able to step back and have a look from a different perspective, but the person who is addicted doesn't get that, they still have this voice trying its hardest to get what it wants.
I found this article and it has some helpful information. I do not know if anyone has tried it but hypnosis works for some people when trying to quit an addiction. In you case it might be worth a try. In the article you can see how hard heroin is to quit, in the list of drugs to quit it was first.
http://en.wikipedia.org/wiki/Substance_dependence
I hope your visit goes well tomorrow. How old is your daughter?

Ditto what the other two ladies said. I can't add anything better. Hope the visit goes well, but just be aware she might try to guilt trip you into giving her the money. And remember that won't help her.

thanks girls,,,, katrina she is 22,,, oh will not bail her out,,,, God put her there for a reason,,, to protect her from herself,,, and to give me a peace of mind for the time being,,,,