Mark and Judy are cool; they've treated me quite well in the last few years and Mark is more than happy to show you his shop and the equipment he uses for fabbing.
Gary is my go-to for materials. He's super knowledgable, stoked about frame building and willing to answer fabrication questions and then suggest fabrication methods (ie: use a chop saw with a bimetal blade to cut tubing, etc). I've sent him cad files and he's provided me feedback before I began my first cut.
if you search the MB, he was the previous speedrail supplier for Denver.
So, I built my entire setup (double-rail, 4-bay) last year buying parts from him and then diamond plate materials from Alreco in Commerce City. It's a stout (although a bit heavy) setup and now I'm tinkerking with concepts for a rear deck and anchor system.
My only dissapointment with my DIY setup is that AAA or DRE can shape pipes to fit within each other if you need a take-down setup for packing in to the Gunny Gorge or somewhere similar...mine doesn't do that and I haven't figured out how to pull mine apart easily yet to fit on the back of a horse...I may just build a 2nd frame for those situations.
here's pics from my build-up last year. All pipes & fittings were from Gary. The towers came from Mark @ AAA.