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Unfortunately, this sounds like a bit of doggy obsessive disorder, which can be one of the hardest things to fix.
First and foremost, you need to strengthen the bond between you and your new dog so that she'll be more likely to listen to you when you call her off the lizards. Taking her to a doggy obedience class will both increase the bond between you two, and will teach her the commands you're going to want to use to get her to stop chasing the lizards.
Secondly, if this is an obsessive behavior, there are a couple products on the market that you could try to help calm her down a bit:
Melantonin is an over-the-counter drug that can be used to treat some anxiety issues in dogs. The dose you would give would be up to 3 mg given orally whenever necessary up to every 8 hours. More information can be found here: http://www.petplace.com/drug-library/melatonin-melatonex/page1.aspx , which includes risks, warning signs to watch out for and other bits of useful information.
Try a DAP collar. These are collars that are impregnated with a man-made version of the dog appeasing pheromone, which is a pheromone that nursing bitches give off to their pups to help them feel calm and secure. It's something that humans can't smell, but it has an amazing effect on dogs with anxiety and other issues. Although you can find them at your vet's office..you can also find them online at places like Amazon.com and Ebay for much cheaper. Just make sure they're DAP brand, as they seem to work better than some other versions.
When I'm dealing with these kinds of obsessive issues, I generally start with the collar and then add in the Melatonin if I don't see a change in the problem behavior in a few days.
If all else fails, you might want to talk to your own vet about trying something a little stronger so that she won't be obsessed by stalking and chasing the lizards.
I hope this helps.