If you're providing resources for the community which are being well-used, then I suggest sending round some emails to various well known hosting companies or o

If you're providing resources for the community which are being well-used, then I suggest sending round some emails to various well known hosting companies or other tech firms asking if they will host you for free in exchange for some sponsorship/advertising. This is pretty common. Also, if youre just hosting linux images, can you not put them on github, google code or similar?