Graphic design, learning software and running a printer/laminator are 3 different things.
For graphic design, there are colleges that just concentrate on that. Some have classes that deal with environmental graphic design (signs are included in that) but there are few who have programs that signage/environmental specific. I only recommend this option if you are planning to be employed or have the time, 100+k, and 3+ years. There are some sign/graphic specific information and classes at segd.org, and you might try sign conventions and a letterhead meet.
For software, there are websites like Lynda.com and you might have some community colleges teaching it.
For hardware, you might try the manufacturer, Roland has classes, and some distributers do, and then there are sign conventions. The best way is being trained on the job. There is another option of a non-franchise company where they teach you basic ins and outs and some equipment training and support. (
www.signbiz.com) I have visited that particular facility and was very impressed with the knowledge base and support they have on hand.
There was a poll here done a few years ago... most sign people are self taught here.