where can I find a great yoga class in Queen's Park or Oxford Circus?

You could try Triyoga in Soho, just off Carnaby Street. They have a great reputation. :)

I know there is a Bikram Studio in Queens Park, just around the corner from the station. I teach Ashtanga, but I am in Bushey, Hertfordshire. I teach either private or small group classes, maximum of 3 people at any one time.

Hi ...there is a place called gracelands in queens park which may have some yoga classes...i dont teach there...as I live further West...also try danceworks and pineapple in west end as they have yoga classes too.

Hi ...there is a place called gracelands in queens park which may have some yoga classes...i dont teach there...as I live further West...also try danceworks and pineapple in west end as they have yoga classes too.

Hi ...there is a place called gracelands in queens park which may have some yoga classes...i dont teach there...as I live further West...also try danceworks and pineapple in west end as they have yoga classes too.

Try West Hampstead Yoga Classes - NW6, so really near Queens Park (on the Jubilee Line).
http://www.nw6yoga.co.uk
Here's a review from a current regular:
Sarah Rourke, Health Consultant & Trainer (West Hampstead Yoga)

“I came to Divya’s class as an almost beginner. I say almost because I had tried yoga several times before and couldn’t understand the hype. Then I found Divya and after one class with her I became an overnight convert. The difference with Divya is her patience and her ability to communicate something she so clearly lives and breathes herself. Speaking of breathing, this is where Divya’s class comes into its own. Other classes I have tried before haven’t talked through the breathing during the poses, Divya explaining this throughout the class makes all the difference to me. I come out of these classes floating on air, ready for the week ahead every time. The impact this is having on my life is fantastic and I recommend her wholeheartedly.”