Where can I find about government Grants to start a small business?

I am trying to get my home business to the next step, but do not have the capitol to make it happen, for unrelated reasons that prevent me from getting a loan. I need to be able to advertise and pay for vendor fees at various shows, but most importantly, I need to establish a real shop for people to come to and where I can work on my product in a more effective environment for my work.