Anyone know what these are? And are those *eggs* stuck all over them? Should I be more worried about the caterpillars or the eggs?

Neither, leave them be!

The caterpillar is a tomato hornworm and the white "eggs" are the larvae of a parasitic wasp that breeds on — and kills — specifically that species of hornworm. Let them kill it and breed and they will become your personal army against future hornworms. Nature at her best!
https://aggie-horticulture.tam...

NMoasis said: Neither, leave them be!

The caterpillar is a tomato hornworm and the white "eggs" are the larvae of a parasitic wasp that breeds on — and kills — specifically that species of hornworm. Let them kill it and breed and they will become your personal army against future hornworms. Nature at her best!
https://aggie-horticulture.tam...

I did some googling after I freaked out - but before I killed them. I put them and the leaves they are attached to back in my garden.

Killed who?
That was the wrong thing to do. I hope that you did not kill anything. Those little teeny tiny wasps eggs hatch and burrow into and kill the hornworm. They are a good insect to have around, the wasps, not the horn worm.

I think Cat1ady meant she did not kill anything and returned them to her garden.
Cat1ady, I'm glad you googled before squishing. You are super fortunate to have those wasps! ,

Thank you Zoe for setting me straight! I did not observe the punctuation marks!

BigBill said: Thank you Zoe for setting me straight! I did not observe the punctuation marks!

Thanks. I'm very glad that I found out what those little white things were before I did anything to them. I remember the caterpillars from when I was just a little kid and my grandparents had a garden. I don't remember them ever getting the wasps though. I'm glad I found this website and google helps too!