So what's essential? I have brown eyes, brown hair and stuff. Assume I have about 50 bucks.

I have brown hair and eyes so if you like my look you could do what i do:

1. Maybelline Dream Matte Mousse Foundation (around £5 a pot in the UK and lasts me about 4-6 months)

2. Beauty UK Line & Define Eye pencil is the eyeliner i use atm but ive found theres not a huge range of effectiveness with eyeliner pencils, I dont really like liquid eyeliner so a cheap pencil serves me well (roughly £1- £2, lasts me about 4 months or so)

3. MUA Shade 2 Pearl white eyeshadow, £1, havent been using this for long but i find it helps a load with making the top half of my face more feminine. A light shade eyeshadow blended well creates the illusion of more space between the eye and brow which makes the area look more feminine.

Aside from make-up i was amazed the difference that a good moisturizer made to my skin. For skin care i use a company called Simple, i dont know if they sell outside the UK but the main selling point ive found is they keep things simple, a few vitamins and minerals and no added colours or scents.

I hope some of this helps

Simple have set up a US website! Im pretty sure i am not allowed to pos tthe link but a quick google search should find it easy enough, simple, smart, affordable skincare products! I use their moisturizer, cleansing scrub and eye roll-on and i heartily endorse all three!

  Well if you weren't on a budget i'd say MAC cosmetic's is the way to go 4sure but since you are drug store makeup brands are a better option. Like El said get Maybelline Dream Mousse foundation, My friend was raving about it so I tried it and I gotta say for a cheap drug store foundation it covers really well. You'll also need eyeliner, mascara and some eye shadow (basic colors nothing fancy). Incase you're wondering I use MAC's Studio Fix foundation and MAC's Kohl Power eyeliner pencil in black and brown. For mascara I use Maybellines The Falsies in black drama and most of my eye shadow is MAC as well. 

  I think you would benefit from talking to a makeup expert and go with their recommendations. I know MAC stores usually have a makeup expert there to help you choose shades that are right for you and also teach you how to apply it.

See here:
Beginner Makeup Starter Kit! (on a Budget) ++ Neutral Makeup Tutorial
May set you back a little more than $50.  First time I went makeup shopping I spent like $60.