Where to look...

I'm lucky to be in computer science, because there's more detailed information about computer science on the web than there is about just about any other subject. Here are the most useful sources of general information about algorithms I've found:

• MathWorld - highly technical, and doesn't describe algorithms, but provides the equations you need to implement some interesting algorithms.
  
• Wikipedia - the good mix of quality and readability in Wikipedia's articles extends to articles about algorithms too.
  
• Google Groups - the noise to content ratio may be a bit high, but this is the best place to go when you don't know what to search for elsewhere or need some gem of insight like "Figuring out the Voronoi diagram of points on a sphere is the same as finding the convex hull of those points."
  

Google Groups is often where I go first, to figure out what to search for on Wikipedia and MathWorld.

Of course, there are also hundreds of more specialized sites out there that are just as useful.