I was wandering if any one had this problem or any one with a fix for it?I can paint with an air brush,paint on computer,can use lead,pen,pastels,colour pencils,chalks and charcoals.But for the life of me I can’t paint with a brush on paper or canvas.Can any one help me with this problem??? 
I too had this problem for years; untill a very very smart woman let me in on the secret.
It might not be the exact same with you, but it helped me so I’ll share what she told me with you…
She told me that it is not so much that I
couldn’t paint. It was that my eye was far too critical.
I grew up sketching, doing everything in utter realism. That was my style and it was all I thought I could do.
When I picked up a paint brush, I discovered that as I worked, I wasn’t getting that same effect. My eye was too critical of the work before it was done therefore it never amounted to anything. Even when I was done I wasn’t happy with it, yet others seemed to like it.
My advice if this is the case? Stick with it. Your mind and perception will learn to relax with your own work and painting style. As you start to accept what it is you are doing your quality of work will increase dramatically.
Well that’s my take on it anyway =P
Thanks CTD - once again you have been a help.My missus always says that it is good and gets the shits with me when I screw it up and put it in the bin.I just can’t seem to graduate the colours at all with a paint brush - I feel i have no control over the brush tip - not like the firm pen or lead.
Hopefully with time I might get it. I am going to go to a art studio here - where all they paint is folk art and bush seneries and see if any of the old ladies will teach me any of their tricks.Fingers crossed.