Help!

As most of you know, my Samantha is not yet potty trained.  She's going to be 4 in less than two weeks.  I have tried to potty train her off and on for a long while now.  The biggest problem is that she doesn't care.  She doesn't care if she has an accident.  If we don't have her in Pull-ups and she has an accident, she doesn't tell me.  She just doesn't care.  Also, if she goes in a Pull-up, she is equally uncaring.  

We have tried bribing her with everything we can possibly think of.  She gets excited about what we will give her, but when asked if she'll go on the potty, she simply says no.  

I was just reading an article on potty training, and they said that if they're not potty trained at this age and they won't go that it's a discipline issue.  I can understand that, and I know she is "ready" but not willing.  She is being stubborn.  

All the stuff on potty training says that you're not supposed to punish for accidents and such, and also not to force them to sit on the potty.  So how do I deal with the discipline issue, without making her not want to go potty even more?  She is a well behaved girl, that does listen when we ask her to do something.  And even is she does agree to sit on the potty, she won't "go" in it.  

Please help.  If anyone has any helpful suggestions I would appreciate it.