What you have there is known as a "grey market" vehicle and you are now a "grey market" vehicle importer.
In certain states it's not hard to liscense a non-USA made vehicle, in other states it's next to impossible.
Most states DMV's just want the money to cover the costs of registration and (if your state collects vehicle cost taxes through the DMV) the tax money.
Your first problem will be with the VIN number. Euro and Jap bikes don't use the same format for VIN's that the US does.
The next problem (if your state requires some sort of a DMV / Department of Safety inspection) is that your headlight, taillight, turn signal and brake lines are not marked "DOT Approved".
Federal law requires this marking.
The third problem (only if you get caught) is the fact that you paid no import fees or duty on the bike.
I don't know about Texas, in Kalifornication (this is amazing) you can register a (example) Kawasaki KX 500 (two stroke dirt bike) for the street. There is a shop in San Diego that sells a kit that includes DOT approved lights, horn turn signals and brake lines. Take your bike to a CHP station, show that it is "legal" and get the form signed by the CHP and take it to the DMV.
On the other hand as of 2000 it's illegal to register an off-road bike for street use in Washington State.
One word of caution:
If you are in the DFW area you "may" want to make sure the bike is 100% legal.
One of the Texas based motorcycle roadracing clubs had a BIG problem about 2 years ago with the DFW police and the Texas Dep. of Safety. Some members were using hot bikes and hot bike parts to race with, they busted everyone at a couple of races who could not produce identification for their bikes.
That bike you have is sweet, but don't let anyone fool you, it will get flat out smoked by any 600 sport bike (GSXR, CBR, ZX or R6) made since 2000. It might be able to hold its own in tight corners, but on the open road it's still just a 12 year old 400.
One other problem you may have is the fact that "authorized" Honda dealerships will not even touch any honda bike that has been grey market imported. American Honda will tell you to contact the market where it was imported from.
There are a couple of websites that deal in grey market import bike parts.
Nice bike!!