dave wrote:
I'd like to make a trolley to move a rather heavy (100lbs) bass guitar amplifier
around. The footprint is 24" x 14". I had in mind a beefy chipboard base in a
Dexian(sp) or aluminium angle frame with 4 spring-loaded or rubber wheels at the
corners. I'm ok with the chipboard! - but trouble is where to get the Dexian/al
angle and wheels? Any supplier details appreciated - as are there any better
suggestion (for the trolly that is :-) )

http://www.screwfix.com/ have lots of wheels that may suit.

Alternatively, wander round a large DIY store, looking for stuff that
might work.