The following is a re-write of my original reply to Alfredo, recreated from memory as best as I can recall:
Just search the 'net! A quick Google search can provide you with more sources of DOS freeware than you'll know what to do with! (There's plenty of other good search engines--Altavista, Yahoo!, et. al--I just happen to use Google a bit. Everybody's got their personal favorites.)
Just do a search!
I did a quick search on the 'net and within seconds, I'd turned up more freeware for DOS than I could possibly ever download.
Yahoo! can get ya started:
http://dir.yahoo.com/Computers_and_Internet/Software/Freeware/
Also check out Completely Free Software--Windows and DOS free/shareware - tested, reviewed and rated. They've got demos and shareware, but tons of freeware as well:
http://www.completelyfreesoftware.com/
There's also the Download Freeware Web site-- a directory of freeware programs submitted by their developers.
Simtel.net provides an enormous collection of shareware, freeware, and public domain software for MS-DOS and many versions of Windows. They've got a lot of really handy freeware DOS programs, categorized by type with brief descriptions and available for download. Here's their URL:
http://www.simtel.net/
Jumbo has a database full of freeware:
http://www.jumbo.com/
Take a look at Mega 16-bit Freeware--they've got loads of completely free software for Windows 3.x and DOS:
http://www.albedo.net/~arvic/
PC-Tools.net has a less impressive collection of DOS freeware than Simtel, but:
http://www.pc-tools.net/dos/freeware/
There's hundreds--likely thousands--of Web sites from which you can find more legitimate freeware than you could ever find time to sift through. All it takes is a simple search.
Search engines are our friends.