If I were in the market for a DSLR somewhere in the $750 range(Give or take) I would be looking at the Canon T2i (I'm a canon guy as well) The T2i has 18 Mega pixles and HD video. For the money I would say its one of the best Cameras on the market currently! Add a 60mm Macro lense ($400ish) and you have all you need to start photographing all your favorite herps.
A couple things to keep in mind when picking a camera
-Brand is important
Though all the entry level DSLRs will probally suit your needs no matter the brand its the lenses that will stay with you after that camera is long gone.
Make sure you choose the brand with the lenses you like/can afford.You will spend far more in glass than the actual camera.
-Do your research
Just like getting a reptile you want to know about the product before you make the purchase. There tons of options out there for the novice photographer enough to make your head spin. I would pick a company research a few of their well reviewed cameras and lenses and then do the same thing with the next company.I would Look at Canon,Nikon and Sony.
-Don't rush your purchase
Theres ALWAYS a new camera coming out with all the bells and whistles. Your camera your buying for $750 today could be worth $500 tomorrow when the newer model comes out.
-Have fun
Photography is a great way to get out and meet new people. Its a great hobby that gives one a sense of accomplishment after you get that excellent shot you were hoping for.
I hope that helps you out a little bit. Fell free to ask if you have any questions and make sure you fill us in on your final decision!