Hi,
You can set or get any custom profile property using the SiteUser object, you can set or get them by their name as documented at the bottom of this page.
if(Request.IsAuthenticated)
{
SiteUser siteUser = SiteUtils.GetCurrentUser();
siteUser.SetProperty(...)
object someObject = siteUser.GetProperty(...)
}
When you try the .SetProperty or GetProperty, you will see the different overloads those methos support, you pass in the name of the property as one of the params.
Hope it helps,
Joe