I have a business plan for making great software product. The product market are banks (finance) who needs this type of product. I have worked in three banks in my country. I have already made one software and sold it, few years ago, to 8 financial institutions (banks). I want to develop different product for banks. First version for sales can be developed in 4-6 months. Software would be sold as a service (monthly ongoing payments). I am an expert in finance (banking). I started learning coding in C# to be able to participate even in coding. Costs of development of first version of product are around 10,000 USD. I can offer percentage of company equity. How can I find an investor who would be interested in investing in startup, who can sell this product worldwide?
I've found great success in using LinkedIn for find accredited investors individually.
Additionally, look at industry-related news websites (GeekWIre or TechCrunch, for example), specifically those who cover funding. Their announcements include the groups backing the project.