I am only 2 years older than you, ([mod edit], so Its okay to say my age
) and I started off with my models much like that...
Unfortunately, I cannot point you in any particular direction, as I am not familiar with that software. All I can say is possibly try and get some multi angles of guns before you model it, so you under stand how it looks from the side, the top, and random angles.
For a uv mapper, just save your model as 3DS and import it into anim8or.
http://www.anim8or.com/
Then go to
http://www.wembley1967.com/pafiledb/pafiledb.php?action=category&id=1 and download AEs anim8or tutorial. It shows the basics of modelling in anim8or, but also shows how to texture in it. Really simple, really cool, really free! Keep at matey,
Yours,
Dan.
Mod note:
Dan,you are not supposed to post your age if you are under
18.