From the site:
iCLIPART.com contains over 7.8-million royalty-free clipart images, photos, web graphics, animations, fonts and sounds.
Every subscription includes professional-grade imagery in formats compatible with virtually all Macintosh and Windows compatible software. Just choose the format you need and click download. It’s that easy! (There are multiple subscription plans — ranging from one week at the basic level to a one-year pro subscription — though the 1-week, 1-month and 3-month site licenses do not include access to vector clipart.)
Single image purchases are also available.