Good to see the term "regexp" (with a "p") in use. I always used to call it that, then at some point realized everyone was writing "regex", and wondered if I'd spelled the abbreviation wrong the whole time. I guess it's just a function of time, it used to be spelled with a "p" and now mostly isn't.
I ended up learning it the same, possibly from the Camel Book? One thing I noticed when I wasn't coding alone in my bedroom and had to actually talk to other coders was that "regex" is more natural to say than "regexp", so that might explain why it became the preferred spelling.
