Note the article's a year old, so the rebates mentioned are all expired :( but still gives a good starting point price for software. Amazon.com has photoshop essentials on sale now for $79. Also, noticed that Paint Shop Pro has $60 in rebates on amazon, bringing the price down to $37.
What you should get really depends on what you're planning to do with the software. The most I ever need to do with my pics is adjust brightness/contrast, crop, and resize - which just about any program can do.