I'm thinking about getting my first stereo setup, and I have no idea where to start.

I'm guessing you could hook up some analog 5.1 or 2.1 speakers up to your computer's sound card.

For $200 you could get this http://www.amazon.com/Sherwood-RX-4105-Stereo-Receiver-Black/dp/B0002EPWC0/ref=sr_1_10?s=electronics&ie=UTF8&qid=1321477148&sr=1-10 , or http://www.amazon.com/Lepai-Tripath-TA2020-Class-T-Amplifier/dp/B0049P6OTI/ref=sr_1_1?s=electronics&ie=UTF8&qid=1321477367&sr=1-1 , and some speakers ,http://www.amazon.com/Lepai-Tripath-TA2020-Class-T-Amplifier/dp/B0049P6OTI/ref=sr_1_1?s=electronics&ie=UTF8&qid=1321477367&sr=1-1 , http://www.amazon.com/Infinity-Primus-Two-way-Bookshelf-Satellite/dp/B0045NCB32/ref=sr_1_7?s=electronics&ie=UTF8&qid=1321477490&sr=1-7 , http://www.amazon.com/Infinity-Primus-Bookshelf-Speaker-individually/dp/B000LKC37W/ref=sr_1_18?s=electronics&ie=UTF8&qid=1321477499&sr=1-18 .

For the passive set-up you need 1 amp and a pair of speakers.

Regarding JRG1990's suggestions, here are my thoughts: I've heard that the low cost Sherwoods have a lot of reliability issues, so you might want to check that out before going that route.  The Lepai amp is a great amp if you don't need a lot of power, particularly if you want a very compact setup.  Don't be mislead about claims of 20wpc, it is less that half of that.  But up to 8 or 9 watts it is very clean sounding and the distortion measures very low.   I use two of these and they both work out well.  One is in a near-field computer setup (either side of the monitor) with some NHT Super Ones, later replaced with Super Zeros with a small subwoofer, and either set-up sounded very good.  The NHT speakers have a sensitivity of 86dB, but since you listen only a few feet away from them they are plenty loud enough.  My other setup with the Lepai is in my garage workshop, driving a pair of Boston Acoustics A70.  These have a sensitivity of 90dB and fill the workshop with sound nicely.  They have a pretty big cabinet so you need some room for them but they put out great sound with pretty good bass, something the smaller speakers cannot do. 

Other than the very low cost Lepai amp (which by the way only has one input, so you would have to manually switch between sources), the best way to go may to buy used, where you can get a lot of value.   I bought the A70 speakers used in excellent shape for less than $100/pr with freshly refurbished woofer surrounds, which is a must for an older speaker that uses foam woofer surrounds instead of rubber.  The NHT speakers I mentioned (which don't use foam surrounds) often go for around $100 a pair.  For around $100 or less you can also buy nicely built receivers that were built to sell for over $500 new.  To prove my point, I have a Denon DRA-635R receiver from the 90's with 80wpc, toroidal power supply, class A circuitry, phono input as well as video inputs, etc that I would sell for less than $100; I believe it was around $600 new.  I don't know where you live, but your local Craigslist could be a source for these, where you could make sure they work and not have to pay shipping which can add a lot to the cost.  When buying used, it is always best to have patience, as good deals come along every once and awhile. 

I actually own and had helped set up several Lepai TA2020 audio set ups and yes 20wpc is rated into 4 ohms so for 8 you'd be looking 10-15 max but i would really suggest pairing these with efficient speakers say 89dB or higher  For $200 and if u need more beef there are several options like stereo amps like JRG stated, more powerful T-Amps like TK2050 and also do not ignore vintage/classic amps like NADs, etc as these paired with half decent speakers give out really warm sounding music but make a point to inspect and test before buying these in the used audio hardware market 

Edit: If you want to stick to 2.0 all the way best not to cut corners and hit speakers that extend low

The Super Zero 2.0 would work without a sub but you wouldn't have much in terms of bass extension only 85hz at -3db they really need to be paired with a sub, the Infinity Primus P163 is 49hz -3db , the alesis m1 mk2 passives are 45hz -3db.

Speakers are normally sold in pairs unless they state otherwise so there priced per a pair and you get 2, yes they would, what output does your pc have 3.5mm jack , rca jacks? , speaker cable is easy just stick to large gauge and you shouldn't go wrong this will do fine for a short run http://www.amazon.com/Belkin-AV23002-25-25-Foot-18-Gauge-Speaker/dp/B0001XGQQS/ref=sr_1_2?ie=UTF8&qid=1321495686&sr=8-2 .

I see that Newegg.com has the primus P163 for $99 each with free shipping.  I have not heard them but their specs indicate that they should work with the Lepai amp.  The Lepai amp has both 3.5mm jack and RCA jacks for inputs (but only one input, just a choice of which jacks to use...the RCA would be preferable).  So you need a cable from your sound card to either one of those inputs.  You can use any 18 gauge speaker wire for short runs.  If you want to listen to a MP3 player you also need a cable for that, which probably is a 3.5mm plug.  3.5mm to 3.5mm cables are very cheap and should be easy to get.  If you order the amp from parts express, that is a good place to order the cables too as their prices are good; newegg is probably also good prices for that too, but I didn't check it out.

Another note on Lepai power output:  it does not put out 20wpc at any impedance.  The power supply is only 24 watts, so you are only going to get around 21 watts total at 4 ohms, or just over 10wpc.  At 8 ohms (like the P163) I measured 6 watts per channel, both channels driven, before the output starts to clip.  The 20wpc comes from the specs on the Tripath chip that the Lepai uses, but the chip specs are at 13.5 volts, much more than a 2A supply and at 10% distortion.  Promoting the Lapai amp with the 2A, 12v supply at 20wpc is a lie.  At lower power levels I measured the distortion at 0.05%, so it is very good (with the tone controls switched off). 

Audiogon might be also worth checking out: this pair of Paradigm Micro Monitor are new and come with a warranty. is possible the seller will let them go for $150 incl. shipping (worth a try). Paradigm's is renown for good-value products.

not sure if the Lepai will have sufficient power to drive the speakers properly (specs). perhaps the local Craigslist for a used amp.

wires from Monoprice, or Bluejeanscables if you can afford it. check your sound card output connectors.

Stereophile magazine liked the Paradigm Atom v.6, the larger brother to the Micro monitor but mentioned slightly excessive treble and loose upper bass so system matching requires care.  Audiogon also has a pair of NHT SB1 for $150 shipped which is a pretty good deal.  This is kind of between the older Super Zero and Super One speakers but has the metal dome tweeter like newer models.   Info here: http://www.nhthifi.com/ServiceCenter/SB1  The Lepai will drive them okay only if you are close to the speakers, like you would be if they were used them at your computer.  Otherwise a bigger amp or receiver would be needed.  Eventually you could pair them with a small subwoofer. 

An alternative to the Lapai amp would be the Dayton Audio DTA-100a, which is a higher power T-amp also from Parts Express.  I have not heard it but based on its Tripath chip I would expect it would sound good, and many reviews say it does.  It also has inflated power specs; you should consider it to be a 30wpc amp, assuming the power supply that comes with it is decent.  This amp would be a good fit for most any speaker.   Its on sale for $90 plus shipping, but add some cables and get everything shipped for free (over $98).  Add speaker wire for $2 (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=109-040) then get the cable for your sound card to RCA.