I guess I will start the flamesuit?
The Klipsch won't work
Heh, well...yes and no I guess. I see 2,000 as a *very* large budget for someone who is just going to be recording vocals....so, i would work monitors into that price so I could accomplish something good...and know that my speakers/ears arn't lying to me.
as my man c7sus mentioned...you'll need several things.
Just to summarize..
Soundcard
Preamp
Microphone
Cable
Monitors
If you don't have a good soundcard, I'd pick up either an Aardvark 2496 which will have 4 preamps built into it. You can record from all 4 of them at once..if you ever needed to. This will run you around 500 dollars...and the preamps are all discrete, have phantom power, and are very good.
I use an Aardvark Q10 and I find the preamps to be quite acceptable (a bit above Mackie XDR in my book).
So, with that you kill the first two birds with one stone.
If you are getting a Shure condensor mic, that is fine. In the 300 dollar range there are a lot of good options these days, so it would be a shame if you didn't check out similar offerings by Studio Projects, Rode, Marshall Electronics or Audio Technica.
I think thats a good price point to be in for a mic though. So, that puts you at 800 bucks. Spend 40-50 bucks and get a pretty nice mic cable that is long enough to work with and fairly high quality for you....your signal chain will be strong.
Then, get yourself a pair of monitors. Something like the Event 20/20bas will do you quite well...and last a *long* time. Others to look into would be Yorkville...maybe the Mackie HD624s. In fact...I saw the 624s for like 750 a pair online somewhere...that is a steal. A pair of good monitors is so essential man...
its your only connection to reality in your studio..
you don't hear anything else - and isn't that what it is all about.
Klipsch will kill ya

I used to sell them at a HiFi store, they have those horn drivers...accented bass response..etc.
BTW - all of that wattage stuff is irrelevant. But, that's another story.
Other options for soundcard would be like a Delta44, with an outboard preamp like an Audio Buddy or DMP3 or something from Midiman.
A lot to digest I know, but...that is a good thing
All of this stuff will work as well for rap as it will for anything else.
That will put your total cost around (500 soundcard/pre) (300 mic) (50 cable) (800 monitors) ...around 1650 or so...at the most.
Should be all you need. But, don't rush to buy...spend a little time researching whats out there. You might regret it.
-Wes