I've been googling around a little bit. It seems like most places are recommending planting the seeds after the last frost which would be about mid-may for me. Isn't that a little late? Don't seeds have some internal mechanism that they know when to come up?

I don't know who told you to just sprinkle the seeds on the ground. To get the best chance of success I suggest you look up each of these plants separately. Not all herbs require the same conditions, either to germinate or to grow. If you only want a few plants it would be sensible to start a small number of seeds in pots rather than throwing a lot onto the garden hoping for the best. And one other thing, rosemary, is quite slow/fussy to germinate.

As with most plants, most herbs can be grown from seed. That said, half of what you listed are perennials, which take a longer time to get to a harvestable stage. I agree with Flora--look them up individually if you want to try all from seed.

Basil is very easy to grow from seed, though it delays the harvest if you wait till its warmer out, so it depends on how fast you want it. I have mine started indoors right now, but they shouldn't go outside until night temps are warmer--above 50ish on average. I generally start 3-5 seeds per space, then thin to two. If you scatter sow like you're speaking of, make sure you thin them to at least 6-8" per plant minimum, more if you're using some of the newer larger leaf varietals. The seed packet will tell you.

Cilantro is also generally seeded, since most of the time it dislikes transplanting, and is scatter sown. My packets say wait till last frost too, but when I do that, it gets too warm and bolts. I would try sowing now, and at the worst, you sow again later.

I would buy starters of the rest, honestly. From seed, you really won't get much harvest this year.