What to buy, or where to start, of course depends on your level of knowledge and skill, and what you are looking for. First of all, if you are looking for an extensive course in jazz theory, you will not find it here.
There are plenty of books with scales and jazz chords, and even plenty of free ones. Just get one for reference.
But if you are looking for practical improvisation for beginners, with audio and TABS, go for the Jazz Exercises CD or download. The Refills are advanced solos, audio and TABS, and explanations.
They all have backing tracks.
If you don't need TABS, but prefer visual instruction, choose one of the DVD's:
Loop Fun - covers many aspects of chords and soloing (video).
Talking Jazz Guitar - covers many aspects of chords and soloing (video), and makes extensive use of the animated fretboard.
Blues Forms - video lessons about all kinds of blues, with animated fretboard.
Private Sessions: video lessons about playing of jazz standards