I've been using Dropbox. You can set up an account there and get free space. Then just use the HLExport utility to package up your date files into a single package. If you want to also make it available as an updatable package like I did with Necropolis you just need to make a XML file for that. If you use the URL I gave for that you can just go straight to that link and make a copy of that one.
The important thing to keep in mind about Dropbox is that if you ask it to give you a link to a file it will give you a link to a webpage where you can download the file, not to the file directly. From that web page you can then right-click on the download link to get the direct link you'll need. I think they also put some kind of "token" at the end of that URL that you won't need. So, for example, the official Deadland Noir file give me a link of
https://www.dropbox.com/s/xk5wli4qldb7ey1/DLNoir.hl?m if I try to share the file. If you follow that link it takes you to a page, not the file we need. If I right click the "Download" button and the "Copy link" I get the following:
https://dl.dropbox.com/s/xk5wli4qld...b0EdGpVelcJ4Am1zno8GuXcBkM7fZGBdIYzOFwzg&dl=1 which is a direct link, but if we include the token part it won't work right. Instead just get rid of everything from the ? on and use:
https://dl.dropbox.com/s/xk5wli4qldb7ey1/DLNoir.hl instead, and that give you a direct link to the file.
In the XML file used for updates, if you check that out, you'll see there are two places in it for download links. The first "download=" is for that final link above, directly to the file. You can also use that for the "website=" link if you want, but I normally link to the first link above, the one that give you a webpage to work from.
Here's an example of what is in my updates.xml for Necropolis:
<document signature="Lone Wolf Updates" version="1">
<update name="Necropolis" date="2013/02/06:0847" size="48" description="Necropolis data file for Hero Lab." uniqueid="0" filetype="3" download="https://dl.dropbox.com/s/nl5jsxr5otygnbt/Necropolis.hl?dl=1" website="https://www.dropbox.com/s/nl5jsxr5otygnbt/Necropolis.hl" companyurl="http://www.dropbox.com/" priority="99" major="1" minor="0" patch="" folder="savage" special="Necropolis" dynamic=""/>
</document>
I think that's about all you'd really need to set up. Then if someone PMs you about it you can either just give them the link to download it or give them the link to the xml file so they can get update notifications whenever you update it. It sounds more complicated than it really is, but I've found it a pretty useful method.