Yes, it is harder to set budgets when you don't have past budgets to go on. Still, even a new company needs a budget. If you do not have historical data available, the process is more challenging, but still manageable. Your reliance on industry information is going to be greater and it will require more research to formulate your projections. You'll need to hookup with people experienced in the Internet and site development, so they can make educated guesses. You'll also want to make sure you break your budget into meaningful chunks, so that you can take each piece and make sense of it.