You can buy one anywhere with now time frame. From when you complete the necessary class and submit the application itll be 6-8 weeks maybe longer before you get the permit. You wont be able to conceal carry till you get the permit. It wont be laminated either so I would laminate it when you get it.
You can go to blue ridge and rent guns and shoot to practice or you can get the gun you want and you can go shoot at the NRA Range in fairfax with it, they just dont rent guns. Both have concealed carry classes, I would recommend the NRA range ones as they are much more professional and knowledgeable. You can go in and get a class schedule from them or check their website.
http://www.nrahq.org/shootingrange/nrahqrange/events.asp
In all youre probably looking at 2-3 months from today till you would have a concealed carry.