It would be a much longer and detailed procedure than I care to post here, but basically you would:
1. Come up with a solid business plan that includes an exit plan after 5 years.
2. Find a venture capitalist or entrepreneurship professor that would be willing to tear your plan apart and give you suggestions on how to make it better.
3. Repeat steps 1 and 2 until your advisor thinks that the plan is up to snuff. Find out from this advisor what venture capitalists or angel investors in the area may be interested in this idea and ways that you could contact them.
4. Contact the VC and/or angels and set up a meeting so that you can pitch your proposal to them.
5. They either give you money or they don't. Then you must decide whether to scrap the idea or continue pitching to other potential investors.
Like I said, this is VERY brief. Some of the details in your plan would include ownership breakdown, board of directors whose members are involved in the industry, as well as others that are familiar with advertising and marketing, transportation, and other aspects relevant to your line of business. You would also want to hire experts in these different fields for your executive staff.
Does that help any? It's not an easy task, but it is achievable.
<edit> There is no real upper limit to the amount of money that you can get. Depending on how solid your plan is and how confident your investors are, millions of dollars is completely reasonable and attainable, provided that your business idea requires it. It's all about the return that your investors will get. If it's any less than 50% within a 5 year period, you're going to be hard pressed getting their money.</edit>