How hard is it to get a job straight out of 25B AIT?

AIT is not enough to land you a position.

Pick up at least an entry level Cert. CompTIA A+ will do (use your own money and don't wait for the military to pay for it) after you do that take a look at a few places like craigslist, and apply to any/every IT Support position out there. The requirements may look crazy but do it anyways because employers build out a wish list which not everybody can fulfil

And last but not least, build a resume that showcases what you are capable of in quantifiable bullets.

Be a sponge in AIT take notes and use that school to build a baseline knowledge so when you do cert up its as simple as ready the book and testing.

Not impossible. Depends on your experience and how you present yourself.

Start applying to technician slots within the active guard reserve. Talk to your higher ips. There's alot of competition but you may get lucky. There's supply slots and the like always open. Look into USAjobs.go and other related sites to see what guard/ reserve components have open.
Good luck