You mention 3 devices and wanting one remote, but aslo something about poor sound from the TV and wanting to get a sound bar?

Not sure of the issue, but if you google Remote Control Codes you will find no shortage of sites with the codes, most universal remotes will work anything you have, from the el cheapo 3-in-1's to the Harmony types, most can also learn incase you have remote you juat can't get a code to or will not work, you can use the existing remote to train the new one.

On the sound bar, are you talking just a speaker set to be powered by the TV audio out or more of a HTIB where the soundbar is powered and has the ability to take say a HDMI input and has a built in amp?

A soundbar would be my last choice and only if I had not way or desire to have descrete speakers for L/C/R and surrounds. Whatever you get it is usually a good idea to add a powered sub-woofer to the mix if you can.