Playing Through the Blues: Trombone Edition is an intermediate-level reading book with accompanying CD (12 listening tracks; 12 play-along tracks) that contains very melodic, fun-to-play blues lines and riffs in various styles and feels. The keys and tempos are comfortable. It's an excellent tool for learning what jazz soloing is all about. You can also improvise over the play-along tracks using the chords for the tracks shown in the book.
Titles: Blues for Michael Brecker * On the Spot * Sus Sounds * Goin' Home * Funky Blue * Blues Ascension * Four in Three * Diggin' In * Nightfall * Medieval Blues * Tradin' Ones & Twos * Shuffle Them Blues.