It's one of those things... if you got flow you got flow if you don't then practice. Self promotion on here leads to public humiliation 99.999% of the time. If you want some instrumentals then go to
http://www.soundclick.com and download some free instrumentals. While your at it sign up for a soundclick account and upload some of your music. They have revolving charts where people vote on your songs and that can help you determine if you got what it takes. I would say if you start maxing out the soundclick charts then it's time for you to start sending out demo's. Everytime this topic comes up it makes me think about the american idol tryouts on that commercial where the people suck but somehow they think they have something special. If your talented it will show even if you recorded tracks on a cassette recorder with the instrumental playing on another stereo in the background. Then if your lucky someone might notice your talent and replace your current cassette studio with pro-tools, professional mic's, and someone who might understand what all those fucking dials do on the input boards. "Anybody with a tape recorder can rap now" - Vinnie Paz
good luck but don't quit the day job... haha