lol
I believe the European is the only hornet we have in North America. But if you think he's a biggy, you should check out the Cicada Killer wasp. If you know what a Cicada is, (that loud ass buzzing in the trees during the summer - some call them locust but a locust is basically a grasshopper), then you know they have to be quite large themselves. I'll never forget my first encounter with one.
No problem. I only meant that if I hadn't known any better, ie; the OP, due to how sure a couple of you sounded on your identification, I would've been led to believe you knew 100% what it was. In this case, being wrong really doesn't matter, however in another case it may've. Even when I feel 100% sure, I'm still hesitant to tell people in cases like this.
Other than that, it's just loads of practice, studying and experience. I wouldn't begin to try and distinguish all the various types of mushrooms/fungus and many of them look all too similar to me, yet I know there are many very subtle differences to the trained eye. I'll list a couple cool bug sites to check out if you'd like. I don't know if they're the best but it's a couple cool ones I've come across.
http://www.whatsthatbug.com/
http://bugguide.net/node/view/15740
lol @ the grass spider and funnel web spider comment. You're absolutely right. Many people mis-id those as wolf spiders and it's even easy for many to mis-id the various funnel and grass spiders, too.