I downloaded from ftp
ftp://distro.ibiblio.org/pub/linux/distributions/tinycorelinux/2.x/
To elaborate a little (using .tcz in this example):
1. Starting at the above url, navigate into the tcz subdirectory.
2. Download info.lst which contains a list of available .tcz extensions.
3. For each extension from that list which is of interest, download <extension_name>.info and read the description to make sure it really is what you think it is. For instance, if you are interested in abiword.tcz, the .info file is abiword.tcz.info.
4. For each extension that you actually want to install, download the dependency file (in our example, abiword.tcz.dep). If no such file exists then there are no dependencies. For each extension listed in the .dep file, recursively follow steps 3, 4 and 5 of this procedure.
5. For each extension that you actually want to install download the extension itself (abiword.tcz) and the checksum file (abiword.tcz.md5.txt) and make sure the md5sum of the downloaded extension matches that given in the checksum file.
Store all downloaded extensions in either your tce directory (to be loaded at boot) or your tce/optional directory (to be loaded as needed). No need to keep .info, .dep and .md5.txt files other than for your own reference.
If you run across an extension that has no .info or no .md5.txt, say something... I downloaded the whole mess (2.x tcz repo, a bit over 1GB) after having some trouble with appbrowser and it doesn't look like I got quite enough .md5.txt files to go around - I'm at work now and don't have time to research further right now - might have just been a download problem.