http://allmusic.com/cg/amg.dll?p=amg&sql=73:196

All of the styles are listed here with links.

Have fun!
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This book features a diatonic (Hohner 580) on the cover, and it’s aimed at Jazz.

http://coast2coastmusic.com/cgi-bin/cart/MSOK63727.html?id=WgItLK8p

I’m not certain about Thielmans. The "Toots’ Hard Bopper" is a chromatic and has a slide, but that just means his name is on it, not that he actually plays it in practice.
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Study music theory — scales, modes, chord construction and how chords and scales interrelate to one another.

Listen, listen, listen to as much jazz as possible, in whatever style especially interests you. Listen not only to other flute players but other instrumentalists as well. The more you listen the more your ear will begin to pick up the phrasing and rhythms of jazz, and the more your playing will begin to sound like the recordings you’re listening to.

There are some self-study aids that you could use. Check out Jamey Aebersold’s Music Minus One series for jazz — a series of recordings of well-known jazz standards featuring a full back up band but without a lead soloist — the idea is that YOU play along with the recording and be the soloist. Another possiblity is computer software called Band In A Box — you either input your own chord progressions or use the songs that come with the software, choose the exact rhythm groove and style you want, and the key, and it will play a full band backup (drums, bass, guitar etc) in that style and key for you to practice soloing against.

But try to play with other people as often as you can – jamming with real live human beings will improve your improvisational skills like nothing else will.
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With all due respect, no, no you can’t play jazz proficiently on a diatonic harp. You’re limited to a select few notes, vs. all twelve notes in western music as well as quarter tones and such with a chromatic harp.

You also don’t seem to understand keys. There isn’t a ‘genre’ constraint by simply picking D major. While most folky stuff is in G, C, or D major, there isn’t a ‘genre constraint’ as you said. Music can be transposed to any key.

And to whoever posted that video …that’s a chromatic harp. The first few notes in Bye Bye Blackbird are ‘A-A-A-Bb-A-A’, which is obviously a half-step, or, chromatic.

Bottom line: Buy a chromatic harp.
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