For Leslie cabs consider MeldaProduction MVintageRotary (currently on sale for ~$30) or MRotary (not on sale ATM but like all Melda plug-ins and bundles goes on sale regularly) although GSi VB3 has a decent Leslie built-in and a separate 32bit cab FX plug-in.
 
The only caution I offer about GSi VB3 is it is only suitable for 44.1/48K sample rate.

This site has some pretty decent plug ins (all free)
http://www.vst4free.com/free_vst.php?id=1346
 
I downloaded the free Vox con and amazingly they worked very well and also I was able automate all parameters.
The link I left above is for the Euthymia Electronic Organ V2 (Hammond clone).
 
 

free soundfont here Hammond Organ B3 con Leslie veloce
 
 link:
http://www.suonoelettroni...0con%20Leslie%20veloce

Songroom
Agreed, the GSi VB3 is a solid choice.
 
I also like the AIR DB-33 (purchased from Audio Deluxe for just $16.99 during a sale). I've used it on a couple and tracks and it sounds great. The rotary-speaker cabinet can also be used as an effect in its own right on an audio track.
 
Both of these titles are available to download as demo versions.

+1 for the AIR DB-33

Not much love for Blue3, huh?  I was talking with someone in the KVR Audio forums about all the comparisons of the many Hammond/Leslie emulators.  This person has the good fortune of owning and playing a real Hammond organ, and he did the ultimate side-by-side comparison test of all the Hammond emulators out there.  He even set me straight about my love for the deep bass growl coming from the VB-3 plugin, which I told him I miss in the Blue3.   He claims the real Hammond organ does not produce such a heavy bass tone. He claims that Blue3 comes closest to sounding like the real thing. (including the Leslie speaker emulator)
Blue3 is only $99 and has a demo version at GG Audio. I highly recommend it.

Love for the Blue 3 here. My Native Instruments B3 had disappeared but the Blue 3 is now my new best friend. Also heads up for the Air DB33 - very pleasantly surprised.

Hey Leee, I really like Blue3 too.  If you're looking for hairy Jon Lord/Goldy McJohn rock Hammond sounds, it's tough to beat.  It's overdrive is killer and there is a huge pallete of useful tone controls to play with.  But if your organ tastes tend more toward Jimmy Smith, then I'd recommend AccousticSamples B-5 Organ V2, which runs within the UVI Workstation.  If you play jazz or traditional R 'n' B or funky reggae stuff, this sampled product is great, probably the best out there in reproducing the power and glory of real Hammonds.  Both Blue3 and B-5 Organ have good Leslie emulations.  I'm also a fan of L'otary.  To go with it, PSP have created PSP B-Scanner, a terrific plug that emulates a Hammond B-3's vibrato and chorus functions, often a weak point in Hammond VST's.

Thanks for the responses, I will check them out. I have Producer. I have been with Cakewalk since it was just a midi sequencer. , version 2 I think.

Yeah... I'm still using the NI B4 and loving it...
 
When I have some cash I am thinking of getting the VB3 so as to have a 64 bit version at least. It sounds the same as the B4 to me...
 
I'll have to check out the Blue3 too...
 
I use B3's constantly! ;-)
 

Sanderxpander
GSi's VB3, without any reservation.

The GSi VB3 is like Gregg Rolie in a plugin! Agreed!