I need a grand piano VST for Sonar X3. I don't suppose there's a good free one out there? I don't need a hole bunch of VST's but I would like to be able to get one if I need it.

True Pianos is bundled with X3. It's quite capable albeit it's a cut down of the full product - you only get the Amber module

Hi Jae. You are spoiled for choice now days as there are many great piano VST''s. The downside is that some of them are huge processor hogs. My goto at the moment is The Giant for Kontakt. Not too resource hungry and pretty versatile. You do not need to own  the full version of Kontakt to use it as it ships with the free Kontakt player.
 
http://www.native-instruments.com/en/products/komplete/keys/the-giant/
 
I don't know much about free options but I am sure someone here will. I think x3 ships with a version of True Pianos, which is probably the best that is included with Sonar, but not what you would call great IMHO. EDIT - I see Jonesey has mentioned True Pianos above as I was typing this post, so it is certainly included!

For a free/donationware grand, take a look a Piano in 162 by Ivy Audio.
 
http://ivyaudio.com/Piano-in-162
 
If you don't have the full Kontakt, you can use the SFZ version. This is a BIG library, almost 6 GB. Samples taken from a Steinway Model B.

If this is a question about the entry level version of X3. I believe the only pianos bundled with it are in Cakewalk Sound Center. To play the sfz version of the piano mentioned above pick up sforzando.

If you want a good piano and use it in sonar look to xln audio.I think they have the best one in pianosound

I don't think free options will get you any better than TruePianos.

My personal wishlist contains Ivory 2 and PianoTeq (5). Depends a bit on what kind of use you need them for. For background duties in bandmixes TruePianos may be good enough. I believe Ivory is something of an "industry standard" but it's pricey and huge. PianoTeq uses modeling instead of samples but that makes it really "alive". I've gotten really good results from that for ballad style playing.

Hi. In the newer versions of SONAR, you (at least I did) get a Demo version of Addictive Keys, which is (in my opinion) are quite good. There is also some free ones besides what has been offered.
All the e best.

Some paid pianos are marginally better than Truepianos, some not even that. The one I found most useful and full of character apart from Truepianos is EZkeyes grand.

Zargg71
Hi. In the newer versions of SONAR, you (at least I did) get a Demo version of Addictive Keys, which is (in my opinion) are quite good. There is also some free ones besides what has been offered.
All the e best.

I have Addictive Keys (and all 4 AKpaks) and was just playing the grand this morning, followed by AAS' Lounge Lizard (Riders On The Storm patch). I was doing a test to reverify a feeling I had after posting in this thread:
 
http://forum.cakewalk.com/Imperfect-Samples-Pianos-Half-Price-m3391575.aspx
 
and yup, I prefer playing modeled velocity-sensitive instruments vs. sampled ones. The AK Grand feels like its got only 3-4 velocity levels. LL responds beautifully to the weight of the key press. I can't wait to play Sound Magic's Fazioli Rose VI. It'll be here Wednesday ($99 in a box via Amazon; $169 online).
 
The problem with many free and paid sampled VIs is the lack of richness (number and quality) of the samples and the  poor quality of the sampling and sample-creating processes. They can be great starters and can often sound pretty good. But the limitations can start to drive you nuts after awhile.
 
And back to sample-based VIs...there are quite a few that are fantastic...and expensive...and BIG. I read a post on here recently where the poster had NINE 2 TB hard drives for samples. Holy crapola!
 
Good modeled VIs are small, load fast and change between presets fast. I have all of AAS' VIs except Tassman. Just a joy to play.
 
If I enjoy playing the Fazioli Rose as much as I hope to, I'm going to have to get their (Bösendorfer) Imperial Grand.