lalimacefolle is bang-on about good rhythm players. To get a different perspective, it may help to listen to the interplay of Steven Stills and David Crosby on the Creosby, Stills & Nash album. The 'rhythm' part is actually done by fingering a chord and picking individual strings. (Slow-mo Shredding? :D)

For Jerry's sound you could try to acquire the same gear, but I think the main ingredients are humbuckers and [u]fresh[/u] strings of medium gauge.