+1 on what suthrn said for recipe building
As for the NN recipe, I haven't done it with extract, but depending on how much grains you want to steep, this is probably a good starting point for the malt bill:
3.75lbs Extra Light DME
3.75lbs Munich DME (Briess is only 50% munich)
1.5lbs Vienna malt
0.25lbs C60
and a clean yeast like Fermentis S-05 or WLP001
Alot more debate on what the hop schedule should look like, but they list the hops at their website if you want to try out your own:
http://www.troegs.com/our_brews/nugget_nectar.aspx