The groundwork for running wordpress would be LAMP - no?
Learning how to convert a Debian package to a PKGBUILD may be useful as well
Then there is the debtap package - also useful - in learning how to convert a Debian package to PKGBUILD
Using the AUR package will require you to read the comment thread on the AUR package and make an informed decision on how to proceed with the ncurses5-compat-lib which is a required dependency.