Thinking of entering the Hazmat arena, where do I start?

1st step in considering hauling hazmat: Seek psychiatric help IMMEDIATELY. If he says there is nothing wrong with you, get a second opinion, or a third...or even a fourth.
Unless you are either:
A. Self insured or
B. Running hazmat about 1 out of every 5 loads, at least when I priced it for me, the cost of insurance is a killer. Any profit you make on 4 loads of hazmat will immediately be eradicated by a substantial premium increase.