i bought a Hawk Arrow II back in 2007 or so, It has been 99% complete since '07 or '08.

What do I need to do to make it legal? I have it nearly ready to fly, but I am told that I have to register it and with it having sat so long, I am not sure what to do to make that happen. Motor has 1 hour on it.
It has a rotax 582, tail dragger, electronic dash.

I am a total newb, go easy on me!

And where do I go to get light sport instruction? If i get my plane legal can I use it for instruction?