Several publishers have issued beautifully illustrated picture books on various composers. I will list several that we have enjoyed, but there are many others in most libraries.
Handel and the Famous Sword Swallower of Halle by Brian Stevens, Philomel Books, 1990
This book is the delightful story of Handel's childhood, his burning desire to play music, his unwilling father and his determined aunt. God intervened through his father's employer, the Duke of Weissenfels, and Handel was finally allowed to become a musician and the eventual composer of the most beloved of all classical pieces, Handel's Messiah!