Where to get steel?

[5150]

I'm not sure if this belongs in here, but here goes.

I'm an idiot when it comes to body work, fabrication, welding, and pretty much any metal work. I have no clue. I'm going to be putting in my 2000 Chevy buckets in my truck and thought I would drill the 8 holes for the seats and put a two pieces of steel under the floor to attach them to. Something maybe 1/8 thick, 2-3 inches wide and 5 ft. long. My question is where do you guys get your steel at. There is a Timken steel plant here in White House, but everytime I've been by there to talk to the guys about different things they are a little standoffish(comes with the uniform).

I'd appreciate the feedback,

Bryan