If you’re in charge of the marketing in your company, there are a couple of websites you may find useful which will empower you to add a degree of professionalism to the material you send out. It’s amazing how effective a stock photo can be when used properly. 

http://www.istockphoto.com (Paid)
http://www.shutterstock.com/ (Paid)
http://www.freefoto.com/ (Free)
http://www.imagefile.ie (Paid)
http://www.bigstockphoto.com/ (Paid)
http://www.everystockphoto.com (Search Engine)