For those looking for the top 500 sites on the whole internet (that is including websites of different languages) it can be found right here: http://alexa.com/site/ds/top_sites?ts_mode=global&lang=none
As for how many websites there are on the internet, I would have to say millions. Alexa only graphs up to 100,000 and tracks through 1,000,000 or so though.
Brian ZuckerGeneral PR Manager, VGChartzbzucker@vgchartz.com