There are numnerous requirements, but right now for most people in your situation are finding it specially difficult. Reason being that now UKBA requires British Citizen non resident sponsor (your wife) to earn the same level of money as they require from someone who is resident in UK.
So, to meet financial requirement, your wife must be earning at a level of £18600 per year before tax. Plus she must have a Job offer in UK, which will pay her £18600 or more.
If your wife does not earn this much money then there is no point even thinking about spouse visa.
But there is another route available, which will work for you, and in that route, there are no visa application fees either, its totally free applications. You and your wife will have to go to an EU country and your wife will have to work there for 3-6 months. After that you can move to UK under EU regulations.
If you think you can manage this way, then I will tell you more detail. You can also try to search "surinder singh route" in google and have a read through.
I would say, just get this done, prepare yourself to live in another eu country for a few months, and in the end you will get very good reward for doing that. :)