They are abundant and available online through several stock art agencies, many of which sell both photographs and illustrations.
Stock images (that includes stock photography, vectors, and illustrations) have many perks for businesses and digital market, but the main, most immediate and evident benefits are the time and money savings.
[2] Stock illustrations fall into two main categories: royalty free and rights managed.
The choice between royalty free or rights managed illustrations depends on buyers' needs.
For instance, royalty-free illustrations may be used many times with few restrictions and for multiple projects, e.g. annual reports, brochures, newsletters, magazines, newspapers, books, and websites, for one flat fee.