Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
So, this guide is for a friend of mine who just started playing League a few weeks ago. He was looking for a champion to play, and we discussed the different rolls and such, and we decided that he would enjoy playing an AD Champion to begin with.
I agree with AD Champs being starter champs, especially the ones I've selected for this guide, due to their ease of learning. A lot of these champions are fairly easy to be good with from the get-go and once mastered can be godly, especially in the level grind from 1 to 30.
I'm not going to be going into each champion, just a basic item build for AD Carries in general. Each champion does have a Skill Sequence and Rune set-up, bur for in depth discussion on how to play these champions, you'll be better off looking up a true guide for said character.
Just as a general rule of thumb, I always start Boots/3 HP Pots. A lot of people will start with a Doran's Blade, which is good for the Health and small amount of Life Steal, but I feel being able to be mobile is more useful in early levels.
On your first Back, you'll probably want to grab a Doran's Blade or two - they are cheap and will help you sustain longer in lane. I generally skip the Doran's Blade all together if I do extremely well, and I'll go right for a B. F. Sword.
I generally just grab the B. F. Sword and a Zeal early for the base boost to Damage and Attack Speed. I always rush the Infinity Edge for my first complete item. The rest is pretty basic for an AD Carry kit.
The Quick Silver Sash is amazing if their team has a lot of Crowd Control - Ahri land a lucky shot with her Charm? A wild Amumu appeared out of no where? QSS to victory. And as far as your Tier 2 boots, Merc Treads/Zerker Greaves/Ninja Tabi is all personal preference. Do you need the MR/Armor/or is your team just dominating the game? Take your pick...