A dremel is good for very short cuts such as forming the tab, or MAYBE drilling the holes, but for general purpose cutting of SS...I would get a shop to cut it for you...That is if you dont have an air compressor...
If you have an air compressor, the cheapest and easiest way to cut would be with a cutoff tool ($15 for the tool + $1 per cutoff wheel)...
Works just like a Dremel, but its air driven and has ALOT more power.
An air compressor and cutoff tool is handy to have, but again, if you dont have access to these tools, then your best bet is to visit your local shop. It is really cheap to have the stuff cut-typically will run under $30 if you have a sheet trying for strips and/or plates.....
As for the type of shops to look for, try the autobody shops, sheet metal shops, and machine shops....If all else fails, look into your local tech school or high school metal shop (You will likely find alot of cooperation at the tech schools!)
Best of luck
"You don't always have to know ALL the answers, but you do need to know where to find them."