Just a word about Taxi if I may. I mean no disrespect to anyone using their services, but in my opinion and experience, I think it's a total scam. Michael Laskow and his team of "formerly's" were one of the biggest mistakes and let-downs of my life. I was with them for 3 years. I submitted over 80 songs in that time period paying the submission fee for each. Of the entire 3 years, I got one reply back asking me to be on a collaboration for something.
I posted my songs to the proper genre listings at all times. 80's rock, melodic rock, instrumental guitar, extreme guitar video music, commercial pop, commercial rock, jingles, the list goes on and on. When I decided to quit because I was starting to smell crap, I shopped my stuff to 5 indy record labels that catered to my style of music. Z Records, MTM Music, Escape Music, Frontiers in Italy and Now & Then records. All of these labels had some of the most popular bands of my time signed to them. In 2 weeks time, I had all 5 of them bidding on me for a record deal. I submitted the same songs to them that I submitted to Taxi and they welcomed them with open arms. A month later after negotiating deals, I signed a contract and started my career. Paid off my parents house, went on tour, started my own life, made connections, gota licensing deal in Japan to where I am a fully signed artist with Marquee Avalon (it's never been easy to get licensing let alone a deal in Japan) and am happy I decided to go off on my own. I also cannot name any big artist that has ever stated in an interview online or on TV that credits Taxi for their success. Please be very careful with this. I went to every seminar Taxi held for the 3 years I was with them.
With every one, came a whole panel of "formerly's". All people that worked for labels at one time, and were fired or asked to leave. Not one person with that establishment had parted ways with a former company on good terms. The only credible person they had talk at a seminar was the president of MCA records at the time who was still the current president at that time. Other than that, just read down the list...everyone is a "formerly".
As for the original question as to how to sell your music, there are many ways to do it, but none of them will get you what you want "for free". You can be the best artist in the world...if people don't know you exist, you will sell 0. Though people claim record companies are dead and difficult to deal with, they open up the doors for you and you get instant results if they are credible. I'd shop my stuff to an indy label if I were you. They handle everything for you and you usually get paid because there aren't as many middlemen. You also do not have to be a big star to make money on an indy label. Way less pressure and stress than a major label.
The good ones will require solicitation which in my opinion, if you go that route, you might as well go for gold. Hire a credible entertainment lawyer that has worked with famous bands, pay the retainer fee that shows you're serious and he'll treat you like a settlement case. If he doesn't get you a deal, he doesn't get anything other than his retainer fee. Don't let the retainer fee scare you. Most people live under the impression that "you should never pay anyone to shop your music." This is not the case for a credible, big name entertainment lawyer with connections. He doesn't need your $5000 retainer fee...it's principal. That's petty cash for him. He won't even take you on unless he believes in you because it will be him (or her) that calls up a label and says "I'm sending you this package...play it as soon as you get it."
The other way to sell songs is to affiliate yourself with someone that has a credible publishing company. Spotters are out there buying songs for pro artists that don't like to write their own material. I've had 2 successful sales doing this with more in the works and I've only just started it within the past 2 years. I'd personally go with a small indy label if you just want to sell product. Let them do the work for you because let me tell you, it's not easy to do this stuff on your own unless you have some money to back yourself. Radio is all about paying a radio marketer as well as the station to play you...so payola still exists. You're looking at $2500 per song per station just to get to the "try or die" section at 12 midnight. Any other radio spots for prime time will be insane. And you know how the advertsing scheme goes...you don't advertise something unless you can do it 5 or more times. At 10k per spot for prime time, you better have some good material IF you can even get the marketer to push it.
The other thing you can do is hire a charter marketer. These dudes know how to work songs and get them into the top 100. The price to make it into the top 75 is like 15k for a credible chart guy to work his magic. For 1-50 charting, you're looking at about 30K+. But get one song to chart at a decent spot, and own all your publishing while you're there, and you'll not only make some decent coin, you can make a name for yourself and this translates into album sales and maybe even a major deal. Doing all this on your own is risky and trying to sell songs on the net without proper marketing is going to get you nowhere. You need credible people in your corner to help you sell this stuff the right way until you can learn the ropes and take it upon yourself to drive the bus.
Good luck in whatever you decide...just be careful and make sure you know what you're doing before you do anything. :)
-Danny