it's a little late to do this now, but at an off-season try doing a 50-50. mention that you're trying to raise funds to start your season and since most people attending competitions are already supporters of FIRST, they're more likely to spend more money. plus, they get half the cash you raise.
last year, in november 2002, 1089 attended Brunswick Eruption and we held a 50-50 total we raised for ourselves a little less than $400. i know it doesn't sound like a HUGE sum, but every penny counts.
hope this helps. if you need anymore ideas, feel free to
email me and ask more about what 1089 found worked last year.