Join Computer to specific OU based on user choice

Hi,

We are migrating machines form XP to W7. There are two environments to which apply two different images. One environment is internal, other external.

Under both environments are the same requirements, to join the comp to AD under specific OU [so that different GPs are applied]. We have managed to do this with internal, where there is WMI query against models, and based on the result, PC is later added to OU with laptops, desktops or VM OU.

Under external, it might be a laptop or desktop to join the same OU.

So the question is, how to make it, that based on user choice, let say: PC-X, PC-Y, PC-Z, it will be added to particular OU?

Any help will be appreciated :)

Kind regards,

m.