There are no tutorials as far as I know.
To run a virtual Airline will take lots of hard work and all of your spare time to make a success of it. Most fail.
You will also need to know how to run one before you start so why not join a good one and be a member for some time before deciding on that route?

PlutonianEmpire,

At first you need to decide on the type of your VA (passengers, cargo, private flights etc.) and also the features you want to deploy.

Then you need to create an attractive website. It is good to browse enough into other VAs in order to get some ideas. If you plan to be stand alone in terms of your VA (I will explain it later) you will also need a database to store information like flight schedule, pireps etc and a good and easy to use interface for the pilots. Try to offer a lot of online database staff in an easy to use way. Schedules, pilot roster, hours and flights flown, fleet data are some examples.

Look for a good web hosting service to upload your website. This is not an easy task as most of the free-of-charge providers will either add lots of ads in your web pages or will not offer good service in terms of server operability, and maintenance service. Maybe you will decide to pay some money in order to have something better. It might also be a good idea to buy a domain like "www.yourVA.com". Many pilots prefer the professional looking style.

Decide on your fleet, find good flying models, ideally with paintkits available and an open repaint policy. Project Opensky and IFDG are good examples of FS aircraft designers, they provide paintkits and they allow you to upload the repainted aircrafts on the web. The also provide a good variety of Airbuses and Boeings. Default models are prefered by many pilots as they are familiar with them but you have to search a bit for FS default paintkits (there are for sure). You must also have some skills in using graphic packages like Adobe Photoshop, which according to my opinion, is th ebest choice for repainting.

Decide where your hub will be located. You will find more pilots if you choose a popular big airport as your base (or offer more than one hub/base). However try to be creative with your destinations and offer routes which cannot be found in any other VA. However do not exclude the popular destinations either.

Once you have all the above ready, advertize. Use forums like simviation, avsim as well as announcement pages available on the web for the flightsimming community to make known your VA. In fact registering pilots is the most difficult part. Also, register your website in the most known search engines and it is a good idea to add a visitors' counter in your "welcome" page. That will give you useful information about how succesful is your VA. If you have lots of visitors and very very few applicants, something is wrong with what you demonstrate to the public. If on the other hand you have very few visitors you should focus in advertizing your VA.

LAST BUT NOT LEAST. Be careful, if you want to use a real life airlíne's name and logo. You must obtain first their written approval ro you may run into serious troubles. Easyjet, for example does not approve any requests for an EasyJet virtual airline.

Now, a lot of people, including me, have problems with setting up a database for their website. If this is your case as well you could try FlyNet (http://flynet.en-studios.de). They have all the database staff ready and you can just create your VA following the screens. They also offer a financial background, simulating economical model where VAs start from a low profile, they hire pilots, buy and maintain their aircrafts and gradually grow. There are also options to lease aircrafts, decide your pilots salary, establish partnerships with other VAs managed by other real people (not simulated) etc. They also offer a forum to backup all this and you can have also a separate sub-forum for your VA. The only drawback is that you start with a low budget which forces you to be a small commuter airline in the beginning but this adds some value to the concept I think. I started in FlyNet about one year ago and my VA owns now 80 aircrafts from which about 20 are Boeing 747-400. So, it is not impossible to become big out of a humble beginning.

Well, that was a huge post but I think it will help you a lot. At least I hope. If have any questions on the above or if you need more information regarding FlyNet, feel free to ask me.

Good luck.

P.S. I really like your username (PlutonianEmpire) 

FlyNet membership is totally free of charge AND free of ads.

Ok, I've tried registering at the fly-net forum, but for some reason, i never got the validation e-mail, even though i typed my e-mail absolutely correct (and i'm sure of it!), and I can't log in. Can you help?

Nevermind. I contacted the admin there and he validated me. thanks though.