If you are a non profit organization, you can most likely get a discount on a vbulletin license by contacting them directly. Otherwise, you will need to pay for the product just like everyone else. Maybe you can find someone who is selling theirs a little cheaper than what it normally goes for. But don't go looking for any hand outs. Starting a business is an investment. You have to put funding into any business to get it started. If you cannot afford vbulletin, then you should start with one of the free forum products already mentioned to see if having a forum will even benefit your business. If so, then invest the money. If you run a successful business, you will make that amount back in no time.