A majority of small business owners and entrepreneurs "bootstrap," meaning that they use their own personal savings to start their business. After an initial investment, you can try to find an "angel" investor who is willing to provide you with seed capital. Angels usually like to see about $50k of your own money put in before they'll consider your idea, although if it's an intriguing enough idea you may be able to get by with less. After than a loan with the Small Business Administration, a line of credit with a bank, or additional money from Venture Capital firms are your options. To really go beyond the initial investment stage, you want to formulate a good business plan, but most importantly you need to show potential investors that you really want to pursue that idea, i.e. it is not something you do while working at your regular job.