What you honestly need:
Half-decent hardware (not certain about the actual specs, they're relatively low)
Co-operative teammates (rare) or friends
Keyboard or Microphone + Skype/Vent/Mumble (And the willingness to use it)
Time to waste
The community leaves a bit to be desired, I'm frequently amazed by the incompetence of random players but I have a blast when I'm playing with friends. However, this community composition was likely inevitable; the game is just a DOTA clone, the DOTA community started out with its head up its ass. That's just a cynical viewpoint though, there's plenty of amiable, decent players on at any time like potentially (hopefully) you.
If you're thinking about trying it out it's (seriously) free and bullshit-free so you've got nothing to lose. I'm usually the greatest skeptic of the free-to-play online games but I've recently given LoL a try and I have to say, it's pretty damned high quality, a lot better than what I had expected anyway.
Also, there is a function to spend actual money on things in game (as I mentioned earlier, the quality of the game is likely due in part to this) such as skins and "champions" but skins are purely cosmetic and any champion can be purchased with the in-game credits which are naturally earned by playing matches, win or loss. You can get by never spending a dime and still unlock all of the champions and runes (the shit that actually matters) if you've got the time to spare (although that's unlikely, it's still possible.)
Alright, now that I've got the sales pitch out there, I'm going to attempt complete transparency. Although this was not my motive for writing the post (and against my better judgment) I'm going to include this REFERRAL LINK to sign up for LoL. That referral ultimately works just the same as signing up normally would, but it happens to slightly benefit me if you choose to play LoL for a bit (up until level 5.) I don't get any snazzy rewards until I refer like a dozen people or more, I've only had 1 completed referral so far which if I remember correctly earned me a temporary boost for in game points. Woo.
In other words, if you're curious about trying out LoL ask somebody you know for a referral link, they'll appreciate the favor. If you don't know anybody who plays or you just want to try it out ASAP use mine and kthx.
Oh and my in game name is Zippomatt, I play Mordekaiser and Sivir primarily but I own a couple more champions who I am attempting to learn. If you desperately want somebody to play with feel free to send me an invite and I'll try to make some time to play a few matches. I'm only around level 18ish (out of 30) so I'm not "pro" by any means but I'm not helpless either. Most of the time I play pre-mades with my 30 friends so I end up getting paired up with 30s anyway; but I still somehow maintain about a 60% win ratio even with the clear disadvantage.