well the average price for a cat back exhaust will be like 350+....the systems that ALOT of peopel are running are the Greddy EVO the Apexi N1 and DC Sports....some people like the Thermal Research exhaust or something along those lines..
it depends on what you have to spend and what price you find them for...
try
www.thepartstrader.com for a decnt price on new/used exhaust or
www.ebay.com www.coximports.com www.civicsuperstore.com these places should offer you used and new solutions for your exhaust..
2 -2 1/4 piping is the largest I would recommend for piping...
