Trucking: CDL requirements/Hauling, dot number, state dot

Question
Hi, If I'm hauling stuff around with a truck and trailer that is classified as a commercial vehicle and I have to have a DOT number will I also have to get a CDL to operate said truck and trailer? See I just started a small welding and hauling business and I wasn't aware that I needed any of those things (the DOT number) I will also be crossing state lines does that have any bearing on the necessity of a CDL?

Answer
Aimee, here are the federal regulations to review:
http://www.fmcsa.dot.gov/registration-licensing/cdl/cdl.htm

Also check with the state DOT in the states you will operate.  If you are hauling for compensation you will need interstate operating authority.  If you are just hauling your tools and supplies you can probably mark your truck "Not for Hire" and avoid the operating authority issue.
http://www.fmcsa.dot.gov/registration-licensing/registration-OP.htm

Hope this helps.
Jim