I just spent a few hours trying to find the online visa application form, I went to http://www.vfs-uk.com.qa/ got an appointment but in order to put all the necessary documents together, it says I have to fill an online application form, i searched for the past few hours and nothing, went to http://www.ukba.homeoffice.gov.uk/ but the only option there is to restart
Were you able to find a link ? What type of visa are you trying to apply for ? I'm based in the UK and this is the most suitable link as you should be able to find the exact visa application you need http://www.ukba.homeoffice.gov.uk/visas-immigration/. Let me know if it helped.