Is there a way to see a player profile over the internet? Is it useful? can I see runes or masteries?
You can do it in-client.
Not entirely sure if there is a site that allows you to but I'm sure there is one.
Do I have to add people to my friend list to check their profile?
You can't do it fromt he stats screen at the end of a game. Once you are in the lobby you can view profiles from your "recently played" list.
leagueofstats.com << no runes or masteries but has stats etc..
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