Getting Back into 40k

So, I'll be getting a job next month. I know, don't cry my many fathers and mothers of the dark city. I've gone from an idiotic 12 year old to a less idiotic teen on this site in the past few years

And, well, I'll be able to put half my pay into this hobby. I can actually get serious about it. As, I was never a serious painter or player. So, I was wondering, where should I start? I mean, I'm going to buy the DE rulebook obviously but I have absolutely no idea what to buy first. Cases? Paints?
In order, here's my plan but I dunno.

Dark Eldar and 40k rulebook (I know diddly about 7th)
Air Brush
Paints (Probably from Privateer Press. I like their paints a lot)
Then Models
Then a case?

I dunno if that's a good order to buy things or not. Also, i'm going to read for myself, but what in the world is played for DE these days?

UPDATE: I noticed Harlequins had a codex. Would they be fun to play?

1.Personally I wouldn't know.
2.I know all of the rule changed from 6th to 7th, not buying the book. But buy the books first.
3.Familiarize yourself with the rules. Get some storage paints ect. (Helpful guides online)
4. Buy a unit you want (as long as you don't want hellions or wyches), learn its rules, continue.
5. After you get a few of the units you want, make a 600-1000 point list, and built until you have that.
6. Once you have all of the models you want (personally, and for your list.) then buy what you don't have/need, or buy more for a 1500 point list.
7.you get the idea

Okay, thanks man! I'm trying to reignite 40k in our place with 3 other players. We're like the most devoted players within 30 miles. Since the FLGS that used to run 40k went out of business we've lost 10 players. However, the biggest game place within at least 100 miles is only a few blocks from my house and they've realized that 40k can bring in more customers(?) so I will probably end up with the nicest looking army in the store... Not that hard really. Over half the guys on this site are better at painting then I am. I consider myself a mid-tier painter. Whilst the other 3 are... they're special cases if you know what I mean. And all 3 of them play marines/chaos marines

Just remember no.1