You have tried "Time-Out", ignoring your child's behavior, and telling him/her "no" but he/she just won't listen.  You are tired of yelling and don't know what to do next.  Below you will find just a few resources that may help give you more ideas.  Behaviors are difficult to correct but you can be successful!  Remember that CONSISTENCY in your response is very important to that success!

Providing Choices to Address Behavioral Issues 
Helping Aggressive Toddlers and Preschoolers

Websites

http://www.scholastic.com/resources/article/that-one/ Asking for your child's input at an early age fosters independence.  Giving choices helps prevent power struggles and tantrums.
www.loveandlogic.com An approach to raising kids that provides loving support from parents while at the same time expecting kids to be respectful and responsible.   This program teaches parents how to hold their kids accountable in this special way. This Love and Logic method causes the child to see their parent as the "good guy" and the child's poor decision as the "bad guy." When done on a regular basis, kids develop an internal voice that says, "I wonder how much pain I'm going to cause for myself with my next decision?" Kids who develop this internal voice become more capable of standing up to peer pressure.