BMW's E46 generation 3 series was sold from 1999 to 2005 and it was known for its well balanced chassis and smooth inline-6 engines. If you want a fast one, you can get the M3 version for less than the price of this next example...but it won't have a 400+ horsepower V8 that'll drink 87 octane fuel and leave twin black stripes everywhere you go. Find this 2000 BMW 323ci V8 offered for $16,900 in Long Island, NY via craigslist. Tip from Jeff.
The E46 generation BMW 3-series was not that much different from the previous generation (E36) but it did take the same basic formula and just up the goodness factor. More power, more refined ride, and a better interior are only some of the benefits of the E46 generation, but one of the biggest changes was that BMW decided to export the wagon version into the US market. Find this 2002 BMW 325ix Touring here on eBay offered for $3125 buy-it-now located in Seattle, WA. Tip from Rod S.
If you've got $15k to spend on a small late model BMW sedan, you might be tempted to buy a 335i from the previous generation...which would be a good choice, but you might not be familiar with how cheap the E46 generation M3s have become. And while a newer 3-series might be similar on paper and in terms of horsepower/etc, but the M cars are where BMW puts all of its technological might -- complete with upgraded suspension, limited slip differential, fancy single clutch automated manual transmission, 8000 rpm, individual throttle bodies and power everything. If the regular 3-series is a milkshake, the M3 is a white Russian. Find this 2003 BMW M3 here on eBay offered for $15,500 buy-it-now located in Midland Park, NJ with a few days to go.
People claim that something is -est all the time. The fastest. The meanest. The leanest. The beastiest. The cheesiest. The frostiest. The greenest. The chipotlest. The cleanest. The best. The sportiest. The raciest. But they are usually wrong -- sometimes on purpose, sometimes through hyperbole, but I'm going to drop an EST on y'all that'll be hard to disprove. This is...the..cheapEST M3 for sale on the planet. It just needs some bearings and a bottom end overhaul...how hard can that be on an 8000 rpm inline-6? Find this 2002 BMW E46 M3 offered for $3,500 in Ventura, CA via craigslist. Tip from Sean.
BMWs E36 M3 was the steal of the market until a few years ago when the E46 M3 depreciated to the point where it makes more sense to step up to the 333 horsepower S54 powered beast that replaced the 240 horsepower S52 after the 1999 model year. Some people might complain about the SMG transmission that you'll find in many of the cheapest examples, but the single clutch automated thing is surprisingly fun to drive, easier in traffic, and can be cheaply converted to self shifted. Find this 2004 BMW M3 E46 offered for $10,800 in Los Gatos, CA via craigslist.
If you want a late model car that looks good, goes fast, and gets lots of middle fingers from other drivers, look no further than an E46 M3. Seriously, I should know, I recently picked one up as a daily driver replacement for my 04 STI...and while the STI got interesting looks from people who assumed the owner was 18 years old and vaping (I assure you I am NEITHER) the BMW gets a completely different amount of disrespect from everyone who assumes you are a spoiled rich brat who doesn't use blinkers (once again, I assure you I use blinkers and am old enough to remember the 70s). Regardless, the E46 with SMG gearbox offers a moderately civilized driving experience on the open road, and a neck-snapping grin-inducing experience on the track that is hard to beat for the entry price...but not for long because prices are creeping up. Find this 2003 BMW M3 E46 here on eBay offered for $14,995 buy-it-now or make-offer located in Midlothian, VA.
BMW's E46 generation 3-series was an excellent driver's car in the cheapest of trims, but it becomes a complete beast in the snarling inline-6 equipped M3 version. If you are looking for a topless 2+2 with a 6-speed manual that is brutally fast for less than $10k, it doesn't get much better than an E46 M3. Find this 2001 BMW M3 Convertible E46 offered via seller submission from Justin.
The BMW M3 was a good car in the 1990s, but the US version had a detuned inline-6 with almost 100 less horsepower as compared to its European counterpart. Thankfully that was fixed around Y2K with the release of the E46 generation BMW M3 with the full monster inline-6. Not only did the world not end, but all of that saved up bottled water could be used to refill the leaking plastic coolant expansion tanks in BMWs across the planet! Find this 2002 BMW M3 E46 offered for $9,000 in North Redondo Beach, CA via craigslist.
Hear that? That's one of Bavaria's finest sport coupes knocking on the door of Daily Turismo's price range. You may enter. Find this 2002 BMW M3 E46 for sale in Olathe, KS for $21,000 via craigslist.
Few cars offer the driving experience of a BMW M3, but they can also be expensive to maintain and costly when something goes wrong. However, prices for the E46 generation M3 are just so ridiculously low these days that I can't help but salivate when I see one of these. Find this 2004 BMW M3 E46 here on eBay
bidding for $8,802 reserve-not-met with $12,995 buy-it-now located in Bohemia, NY. 
As the E30 M3 market continues to rise the inevitable question is when will the E36 M3 market follow suit...and it's possible that low mile E36 examples are already on the rise, but the bigger question is, has the E46 M3 market hit rock bottom? If not, how low can it possibly go? Find this 2001 BMW M3 E46 offered for $8,000 in New Canaan, CT via cars.com. Tip from Steven.
This next feature comes as a "friend of the seller" submission from Rich who writes my friend from church is selling his BMW M3...it would be a blast to see his car on DT and show him that I submitted it. I think he'd really appreciate it. Rich- You had me at M3. Find this 2003 BMW M3 offered for $19,500 CAD ($14,704 USD) in Winnipeg, Manitoba, Canada, via kijiji.ca. 
The C5 Corvette Z06 might be the fastest unmodified vehicle you can get for around $15k, but that doesn't mean you want to buy one. The Z06 has 265 mm wide tires on 9.5 inch front wheels make for lots of grip, but it also can feel a bit numb, and the stock fender gap looks like the Z06 is ready for the Paris-Dakar rally. Additionally, the car is so bloody fast that any attempt to enjoy the limit on or off a race track involves significant risk to people, pets, and other things...so there has to be a better way. What about the best handling** car for the same money? This is where BMW's E46 M3 comes into the picture. Find this 2006 BMW M3 E46 offered for $15,500 in San Fernando Valley, CA via craigslist.
There are few cars that will match the E46 M3 performance per dollar ratio. Not just few cars, probably none. This E46 M3 hits 60mph in about 4.7 seconds and trips the 1/4 mile lights at 13.5 seconds and 105 mph. In case you were wondering, that is fast for a street car. But it isn't just a one trick pony, the E46 also features one of the nicest handling chassis this side of a Ferrari...and you can get one for about $10k. Find this 2003 BMW M3 E46 offered for $9999 in Philadelphia, PA via craigslist. Tip from K2 Mystery Car.
In 2001 with the release of the E46 generation M3, BMW finally offered the North American market the same power that had been enjoyed in Europe for years. Previous North American M3 versions had de-tuned and catalyst neutered engines, but the E46 generation was a world car, meaning everybody got the same screaming inline-6 to go with the nimble chassis. Find this 2002 BMW M3 for sale in Seattle, WA for $13,000 via craigslist.
currently bidding on ebay for $1,025 with 3 days to go in Brooklyn, NY.