Yes, and they can be found at the Official Axis & Allies FAQ anonymous
ftp site at ftp://ftp.indirect.com/pub/rpg/axis+allies/variants/.

Many thanks go to Britt Klein for maintaining the site.
If you want your variant or house rules stored there, please send
Britt (tierna@indirect.com) a message telling her what it is
you would like to upload.  She is *not* accepting ftp uploads; file
submissions are being taken by email only.  Britt can answer any
questions you may have about how to upload your submissions.

Also, another good A&A ftp site is maintained by Marcus Augustus Alzona
(Marcus+@CMU.EDU) as follows:

ftp://ftp.octopus.net/pub/axis+allies/