My mom just picked up a glock and put close to a thousand rounds through it.  She's consistently hitting left and asked me to adjust the sight.  I don't own a glock and don't expect to buy one so I'd rather not buy a dedicated tool.  Is there a decent universal sight tool, otherwise I'll just use a brass punch which isn't quite as nice to do.

I recommend before you start moving sights around, have your Mom try putting more finger on the trigger and see if the resolves the issue. It's a common problem with glocks shooting low/left for new glock shooters. If that doesn't work, the factory glock sights are polymer and I would take a punch to it. They are typically easy to move.

You should shoot it to see if the sights are actually off. As already suggested extended dry firing sessions may help her stay lined up. I discard the standard sights on Glocks the second I buy them.

I'm using Trijicon and Warren Tactical sights and most gun shops will install them for free if you buy them there. Go to a shooting range to make the purchase so she can test the zero after installation. Adjust accordingly.

I know Glock uses the plastic sights for economic reasons, but a quality firearm deserves better sights. I purchased a Glock specific sight adjustment tool from Top Gun Supply, $120.00 if memory serves me well. Most people are unwilling to invest in premium tools.

You can get a sight pusher that works great on ebay for 40 bucks, I forget the seller but it's the one sith a ton of sales.