Hi Michelle,
I don't know anything about beneficial insects, but one thing I found works pretty well at controlling thrips here where I live in Oregon is a piece of bright blue foam that is found in a craft store or some meat markets use this same color blue to package their meats. I put staple it to a garden stake and then put tangle foot on it, place it right next to my plant that seems to attract thrips. I lost a whole bed of glads to thrips last year unfortunelty, I did not know about this color blue attracting them until later. If you do this soon enough it will bring them to a small toloration.
Now I have to get some out soon before they start multiplying.
Kathy

What is tangle foot? I am willing to use it.

It must be something sticky that traps them. Have never used it myself, but it looks interesting.

Here is a link that might be useful: Tanglefoot

Michelle, see my above post to miss em about my experience with beneficial nematodes. I have no experience with the thrip predators, tho.

Anna