If you follow this link, you will come to a page loaded with recommendations for complete Richard Wagner operas, as well as highlight discs of these works. This is a list of the best recordings available. You can buy them at my Wagneroperas.com megastore website through Amazon.com.
Among the recordings you will find are the fabled live Bayreuth recording of Tristan und Isolde with Birgit Nillson and Wolfgang Windgassen, as well as the complete Ring Cycle conducted by Sir Georg Solti. Check it out!