I'm just starting to get into this whole painting thing, and I figured this would be a great place to ask- what sort of primers do and don't work for model painting? Will regular spray paint primer from the hardware store work or should I be looking for something different?

I have used krylon spray primer that you can get at walmart. I also when the weather is not so good use badger airbrush primer. It is called Stynylrez and you can use a brush with it but it works great in an airbrush.

I use the Citadel black primer which comes in a huge can but at a hefty price. I still recommend it, since it gives you a very smooth, even, matt black base to work with and I never had any issues with it. I also recommend pre-shading your minis. You do this by fogging the primed black figure with a white colour spray evenly from all directions in a 45° from above. This will instantly give you an indication of where light hits the mini and which areas should be lighter, and which areas should be darker. If you use thinned-down paints over the pre-shaded figure, it will also give you instant highlights and shadows which you can leave like that, or use as a base for a more intricate paint job.

I recommend Tamiya brand primers. The mist seems to be finer than the dollar rattle cans and has never muddied my figures' details.

Also, avoid priming when it's particularly hot. The paint will begin to dry before reaching the model and give you a bumpy, textured surface. Avoid overly humid days too.

And NEVER use the rattle cans indoors!

Second the Tamiya, the Fine type is actually mental. The regular is good as well. I used army painter before this and the difference is immense.

In UK Halfords Acrylic sprays are great and less than GW

Wilko (UK) hobby primer does me pretty well.

http://www.wilko.com/specialist-paint/wilko-primer-spray-paint-white-400ml/invt/0413848

Tamiya Fine white is mental. I was using army painter and it legit ruined my officers with a **** coat.

I found the Army Painter white gave a very bright white and smooth finish that was a little bit difficult to paint over when used on heroes, but which was pretty much perfect for Stormtroopers. I'd prime them, paint the dark underclothes areas/helmet detail, give them a dilute wash, and then they'd only need a tiny bit of highlighting with Vallejo Gloss White. It took the time per figure way way down compared to priming with say Citadel Corax White. This was important, because by the 12th or so variant Stormtrooper , I was losing my sanity.