New horse questions

I haven't tried too hard to look this up yet in my horse book I"ve recently aquired, but Bot flys were not listed in the index-

I was grooming Lacy yesterday snd I found some little off-white things stuck to her fur-particularly under her arms -I had to pull so hard with my nail, 9 times out of 10 the whole hair came out. I asked the farm owner's about it and they advised they were bot fly eggs and that they did give the horses something to kill them (I didn't ask what) but that it didn't stop the eggs from being laid. How do I get these off her? Do I need to get a lice comb or something?

Laurie-if you see this-I began getting to know my lessons instructor. I am really starting to like her a lot. I am now considering boarding Lacy at this particular stable until I find my "perfect farm" to move into. And using her as our trainer. What are some things I should look for? I've noticed the horses she trains are exceptionally trained-they look where you look, and seem pleased to make her happy. She moves very slowly and deliberately around the horses and seems to know every single quirk down to the most minute detail on every horse in the stable. I've been so impressed with her lately, I confided in her about Lacy. She was actually excited and began to talk to me about this horse she helped with down the street that had cancer and had an eye removed. So she actually has some (admittedly not much) experience with it- helping that family to get to know that horse(she'd been uncatchable in the pasture and untouchable as well) the horse was a rescue that was placed with them. She said they'd actually get down and act like horses in the pasture-and the man would do it for hours and hours and hours until he could finally just touch her, then go away to act like a horse again, and they went from there. I thought that was SO cool!
I'd appreciate any tips.....I bet I could find that on your site - going to look now.....