[Gabe]

First off, try going door to door in your neighborhood. It worked for us and we raised $500 that way.
Next on the list, is there a Starbucks nearby? They were really friendly to us and we did a demo there and it helped with another couple hundred.
Ask family for donations. They will understand that you did not expect to do so well and need emergency funding.
Ask your school for a donation in the order of $1,000 to $1,500, which I think is reasonable. Do not as for too much from your school or they will say no.
Set up a dollar-for-dollar challenge with a company that you know is friendly toward you. The way it works is that you raise, say, $1,500. Then the friendly company promises to match that amount.
Now comes a very delicate arrangement for raising money. Ask one or two individuals to finance the trip to Nationals for this time, with the understanding that you will repay every single penny back after you return from your trip. The reason why this is so delicate is that this person has to trust that the $5,000 to $10,000 from their savings account will most definately be paid back. There are people out there (most likely a wealthy family member) that will do this, but only if they believe you when you tell him/her that they will be reimbursed.

Our team knows your plight all too well. Last year we were a new group of friends who went to the Pacific Northwest regional in Portland, and had no idea that we were going to win first place. So in the same time that you have now, we had to raise the same amount of funds to get to Atlanta.
I hope you do well at Nationals because from all the posts at ChiefDelphi, you are an excellent team!