I've done two amateur comps, and both times purchased my spares at Meijer. I spend a LOT of time looking at all of the available racks there looking for racks with consistent thickness, straight bones, etc. But, what do I know... 2nd place out of 25 and 3rd place out of 62. Don't listen to the discouragers... get some good looking ribs from wherever you can, trim them nice, do what you did when you practiced and have FUN at your first competition! You'll be hooked as long as you have fun and you'll probably make a couple of new friends along the way!