I just bought a slide trumpet for my niece. She used to play trombone. Are there any good books on or for slide trumpet? Should she just get trumpet music? Any hints or help will be appreciated. Any one here play slide trumpet? I here it sounds better than the valved trumpets. I play a regular King trumpet myself.

Slide trumpets lost popularity when the valved trumpet was invented, I didn't know any still existed I doubt there are any books or music for it. I would suggest just a regular beginners trumpet book for lack of a better option.
watch out though switching between trombone and trumpet will screw up you ambusher, its best to pick one and stick with it

The slide trumpet is interesting and can be well played. It is a difficult learning process as the slide positions are so close to each other that it is all too easy to be sharp or flat on a note. But if the artist has a good ear the slide trumpet can be played perfectly in tune and that is not true of most instruments.