I've been talking to a bunch of the 6th Gen guys, and they have been getting the Acura TL-S type sway bars for a cheap but great suspension upgrade. I've hear you can pick them up for around $60-80. For a strut bar, anything will do. I've got the Nu Speed bar. As for springs and shocks, it depends on what you want. If you don't mind spending a little extra, coilovers are a great option. I can answer coilover questions for you, but for springs and shocks see what the other guys will say about that.