Does anyone have any recommendations (or links) for good, professional fonts that are often found in logos? I know these often cost money but there should be a similar substitute that is free?

I am looking to get a logo designed for a web 2.0 website. Examples of good logos would include: digg.com, friendster.com, dodgeball.com, myspace.com. These fonts are all unique and I wouldn't be surprised if they were custom designed, but I'm looking for futuristic fonts.