Sportscotland has a useful page with links to various funders here.
The Scottish Sports Association has some useful links here
The Scottish Council for Voluntary Organisations has helpful advice here
The ALDI Scottish Sports Fund Application is now open here
Your local council will often have a volunteer service which may provide help with funding, or have a specific funding officer. Search on their website for details.
Several clubs and facilities have been successful in applying for funding. You need to have a clear idea of the project for which you want funding, with accurate costs. Funding can often take several months to come through so plan ahead.