playing book files 1-9, then jumping to next file in book

Hi, I hope that someone can help me.  I listen to audio books mostly on my sanDisk 4g player. Some of the books i have multi files for each recorded disk/chapter,mostly the older books out in audio about 10 years ago.  What is happening is the mp3 player is playing the files 1-9 in the chapter/folder then goes on to the next chapter/folder 1-9.  this is when there may be 50 - 70 files for each folder/disk.  the book is covered in 8 folders in the one book folder.

is ther some program I can use that will get this fixed up so I can play the books on the Sandisk mp3 player?

Thank you for any answers or ideas  that I can try.

Denise

Use the free program MP3Tag to arrange the track number tags so they play in the correct order.