Slightly self-promotion, but you can get a variety of old perl sources at http://www.etla.org/retroperl/ (collected by someone non-me, I can't remember who though)

I had thought someone had done a perl 1 release that built on modern systems, but on a quick hunt I can't find it.

The perl source repository quite many historic releases also, and the first few commit messages also contain the accompanying release notes.

See for example https://github.com/mirrors/perl/commit/8d063cd8450e59ea1c611... for the perl 1.0 annoucement (click on the [...] link to get the full commit message).

ooh, cool, I didn't know that was there.

My more active interest in perl was pre-git :)