Ok, this is what I understand about aquiring a short barrel shot gun. Am I right?
I own standard hunting shotgun with a 20 inch barrel.
I get BATF Form ? and use it to register my shotgun, get required signitures, get fingerprinted, follow all instructions, and pay $200.
Wait and wait.
Receive aproval for registered SBS.
Cut barrel down under 18 inches.
Nothing else, no renewal fees or re-registrations.

You have it exactly right.  The form you want is Form 1 and will need all the ingredients you mentioned.  There is never another fee or tax to be paid unless you sell it,  

Thanks for all the help. I just get pissed off trying to read legaleese.
Edited to add
This would be an NFA weapon, because it is covered under the National Firearms Act. More specifically AOW, any other weapon?  and even more specifically a SBS, short barrel shotgun.

Quoted: Thanks for all the help. I just get pissed off trying to read legaleese. Edited to add This would be an NFA weapon, because it is covered under the National Firearms Act. More specifically AOW, any other weapon?  and even more specifically a SBS, short barrel shotgun.

Yes, it is an NFA weapon, but no it is not an AOW. If your shotgun has a buttstock, then it cannot become an AOW, only an SBS.  AOW shotguns can only be made from either virgin shotgun receivers or shotguns that have never had a buttstock attached, like the Mossberg Cruiser.  When you see a shotgun that is an AOW, what you are looking at is not really a shotgun at all, legally speaking, but a Smooth-Bore Pistol.  Big difference.

Making an AOW out of a shotgun receiver goes on a Form 1 just like an SBS and a $200 Making Tax is also due.  The process, cost and hassle are identical. The difference is that if you make an AOW (again using a qualified shotgun or receiver), you cannot legally put a stock on it.  On the other hand, if you make an SBS, you can have the stock or remove the stock and make the shotgun identical to the stockless AOW you had in mind.  You can go back and forth with an SBS, but the same is not true of an AOW.

Also, making an AOW is not cost effective as it costs a $200 Making Tax to do it yourself or you can have a Class 2 Manufacturer make and register the AOW for you, then transfer it to you for only a $5 Transfer Tax.  Everything on a Form 1 is a $200 Making Tax regardless of what you are making, but Form 4s are a $200 Transfer Tax for MGs, suppressors, SBS, SBR and only a $5 Transfer Tax for AOWs.