Programming

I'm very lazy so I'd probably start by looking at filters on those sites, if i really wanted to tackle this with programming, i'd:

see if there's an api, or rss feed for these sites, if so i'd pull that down with a cron job and do filtering locally with probably regex.

if not i'd scrape the html and pull out the relevant links with whatever the latest html parser is for the language i use (i.e. it used to be beautiful soup for python, but there's i think a new better one).

but as i said i'm rather lazy, and haven't been on the prowl for jobs for some time.

This may be a good place to start. Most states (that I'm aware of) have workforce development programs with both online tools and physical offices with available assistance. For most state governments it is beneficial to retain high skilled and high paid workers as part of their tax base, and provide employment opportunities to low skilled and low experience workers to increase their contribution to the community.

You should be able to find automated notification tools on their web offerings (or even an available api), and their physical locations can be excellent resources for developing soft connections with the proffesional community in your field.

Best of luck in your search!