Sources for raising initial capital

Hey, I'm doing some research into the different avenues for raising capital for a new fund. Would anyone have any insight into whether anyone specialises in providing fund capital? More specifically a mezzanine fund.

From what I've seen so far the options seem to be placement agents, distribution desks in large banks, funds of funds and seemingly some private equity houses have also gotten into this area.

I'm just getting the feeling I might be missing some group specifically designed for this area, in that all the do is look for start-up funds to invest in. Does such a place exist?

Are there other areas I should be looking at?

Thanks!