In today's world, it is so important to have a strong web presence, no matter the business. You can create an inexpensive and professional website, with no necessary coding, on sites like wordpress.
Sites like LegalZoom are also pretty good for getting your business entity formed at a low cost, and have done a good job in my experience.
It sounds like you may be forming a mission -driven nonprofit? If so, it is likely worth consulting your accountant on ways to fund the business start up costs, as there may be tax benifits.
First make your website and start marketing online using different way like Email marketing, free ad posting website, and many other way you can advertise your business.
You can also hire professional SEO for your website ,
A credit card will get you pretty far depending on what your going to do exactly. You need a website and there are legal fees. That's less then a couple thousand depending on how you go about it. Using your time is the biggest way to save money. What are you doing when you say promoting cultural entertainment?