Don't start!!!!! It's habit forming. I went from the little Aquarium net to the nylon stocking & next thing I knew I was taking Aquatic Entomology courses. I then joined a watershed association & started up as a stream sampler. Next thing I had to have a camera that took decent macros . Now I'm doing an in depth (Pun) stream study on the river I fish. There was a lot of "professional" stream improvement work done on the river & I'm seeing how much damage was done. I now have a $100. D kick net, all kinds of seines & bottles,trays etc. I even went so far as to get a cheap digital microscope. Well to put it in perspective I don't have much time to fish,but I sure know what flys to tie. & I would tie them too if the damm dog had'nt sniffed out my feathers & fur & ate most of them.
Want a good book , look a the book "Bugs"
want a good PP presentation
http://www.nwnature.net/macros/docs/know_macros.pps