adding a border is simple.
press ctrl+a to highlight the entire banner on the new (top) layer.
Go onto edit>>>>stroke and on settings put it as one px black on the inside and it tends to make the banner look better.
Anyway, as it comes to it the new banner is actually very good for a first banner in ps, but is nothing all that spectacular.
It's not bad but there are quite a few thing's taking away from it's quality
1) the main cut, namely it quality. It seems quite blurred and doesn't look very good. For pre-made cut's until you want to cut them on you own try
www.evolutiongfx.com/wrestling.html and download pre-made cut's. Most of them are of high quality.
2) your second cut doesn't look all that great in quality either, but as it's blended in it look less noticible. Also, it's placement isn't all that great and really blocks the third cut behind it.
3) it need's a proper border, look above.
4) The bg's a bit lary and the bics in the bg don't really stand up against it much.
5) the text has too much glow and the font isn't very good. Try
www.danfont.com for more font's to download.
Don't get discouraged though, your better than a lot when they first start, if it makes you feel better my 1st, 3rd and 4th banners are below ( i think I deleted my second

)
So you can see your not doing bad.
If you need help with any of this feel free to pm me on msn.