I did a search for "fonts" on Google, two of the top results had sections to "submit a font". That's where I'd start. Although, I bet the cut you get per sale is horrible. I won't link them here because I'm not interested in promoting them, I use free fonts from dafont.com for most of my stuff. If you're just getting started, you might be better off giving your fonts out for free until you establish yourself in the community, then think about designing a whole font family to sell.
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