I didnt know if there was a list somewhere of the more popular BTC exchanges. I have been searching. I found Kraken. It appears to be laid out nicely. Id like to look at a few that allow trading in smaller amounts for someone just starting out.
Try to see on what information you need regarding on exchangers here
https://cryptocoincharts.info/markets/info and you can find some interesting facts about on which is the top cryptocurrency exchange existing today. But for that listed on this site I will recommend you to do your trades on the bittrex since this platform is so easy to use and not so sketchy.