There pretty much dead already. I've only seen a few new releases on DVD-A but some labels still produce SACD. Telarc/Heads Up seem to be the most prevalent. I too collect all of the formats you mentioned. I currently have about 300 albums in my collection and I rarely listen to anything else on my system.

Try ordering online through places such as www.elusivedisk.com, www.acousticsounds.com, www.amazon.com, etc. I can give you a list of several others if you want. The first two will yield better results then amazon.com

Happy hunting!