The first thing you'll need for your bowling fundraiser is a venue. Shop around for alleys that will give you a good deal - many will give you significant discounts on however many lanes you need if you agree to host your tournament at times when the alley is normally slow (usually weekdays during the day).
Corporate sponsorship is a great way to start offsetting costs and bringing in profit for your bowling tournament fundraiser. Offer local businesses advertising space, logo placement on tournament banners, and newspaper advertisement, in exchange for set donation amounts. This is a great way to get larger chunks of money in all at once, and can create quite a buzz around your event.
Advertising your bowling tournament fundraiser is a must, as the more well attended it is, the more money you will make. When people arrive, have plenty of opportunities for them to donate - snacks, drinks, and raffle tickets are all great ideas. If you can get a local bowling retailer to donate some raffle items, that will help maximize profits even more.
Lastly, get the players involved with personal sponsorship. Ask each bowler to aim for $100 each in personal sponsorship. Many will get competitive and try to out-do each other, which is great both for player morale and for your organization. The more you can get people fired up about this bowling tournament fundraiser, the better it will be for everyone.