If you have Dimension Pro it has some usable and very tweakable hammond samples - see this post
http://forum.cakewalk.com/FindPost/2877651 NI's B4 is no longer available so unless you are extremely lucky to find a copy second hand, remembering the licence has to be transferred by NI to your account from that of the previous owner, something that you would need to fully check out before parting with any cash.
GSI's free Organized Trio has been mentioned, its good but there is also the full version VB3 which many will argue is better than NI's B4.
http://www.genuinesoundware.com/?a=showproduct&b=24 NI replaced B4 with Vintage Organs, a Kontakt instrument. You still retain complete control of drawbars, leslie speaker etc, but the hammonds are arguably not quite as good as the old B4, however there are also some very nice transistor organs in the package.
If you have Dimension Pro it has some usable and very tweakable hammond samples - see this thread
http://forum.cakewalk.com/FindPost/2877651 Orange Tree samples do a very nice lap steel guitar and an acoustic slide guitar, but they need the full version of Kontakt to run.
http://www.orangetreesamples.com/lap-steel-guitar