A good image editing program is essential to your art website. Not only will it help to make your images look professional, you can resize and compress the images so that they take less time to load. Here's a short list of image editing programs to get you started:

• Programs for purchase:
  Benefits: user friendly, comes with help files and guides.
  
  
• Adobe Design Premium CS5 - Dreamweaver for web design, photoshop, illustrator, and more - everything you need!
• For anyone new to programming, the best option (my opinion) for designing a website is Adobe's Creative Suite, because it includes EVERYTHING you need to build seamless, professional webpages. Image optimization is so important for an art website, and having photoshop included makes this ideal, if you have the funds!
• Save $35 on PaintShop Pro Photo X3 with coupon code
  
  
• Free programs:
  Benefits: free!
  
  
• Gimp GNU Image Manipulation Program - I use this program often, it has a ton of great features! There is also a portable version - these versions are great if you need an image editor on a work computer, etc. when you don't have administrative rights for installing software.