I use Native Instruments Komplete 8 Ultimate, which has a bunch of synths in it. The flagship program of theirs is a sampler called Kontakt 5. I have something like 240 GB of samples for that program. I also have the complete set of E-MU Proteus sounds for Kontakt.
Another of their synths is FM8, sort of like a SUPER DX7, on steroids. For that, I also have a GIANT set of sounds, essentially every single factory sound for any of the DX-type synths Yamaha ever made - there are 20,000-30,000 sounds there, all nicely converted for use with FM8.
Then it also comes with Reaktor 5, which is a real cool synth that lets you combine modules of the various types of synthesis, to create pretty much any kind of synth you want. I have one sound that was literally created from looking at the original circuit design pictures for the home theater organ Pete Townsend used for the beginning of Baba O'Reilly - it sounds PERFECT. Another sound I have is an exact replica of the monster rotating organ sound from Won't Get Fooled Again.
I also have some VST instruments - a Minimoog, ARP 2600, and some others.
In addition to Sonar X2a, I also often use a VST host wrapper called Forte, from a company called Brainspawn. This is a synth-rack program, allowing complex layering of sounds from any VST instruments and effects - TOTALLY sweet for live performance.
I use 2 controllers - one is an Axiom 61 Pro, and the other a Yamaha.
Bob Bone