Well, first off, I would suggest to get 15 lbs of live rock for your tank. You can get that either at the lfs or from someone who is taking down their tank. ( lfs will charge you an arm and a leg for it, $10 a pound or more
so its generally quite a bit cheaper to get it from someone on here.) If you dont want all live rock, you could go with part base rock and part live rock, but for beginners I would reccomend you start with just live rock.
Sand can also be obtained from someone on here, and whether you choose a shallow or deep sand bed is entirely up to you.
For livestock, you could probably put about 3-4 fish in there. ( I have 4 fish and a large shrimp in my 10gal, but its pretty crowded )
Some ideas for fish:
-clowns ( occelaris, percula )
-gobies ( neon, trimma, firefish, clown )
-damsels ( three spot, yellow-tail )
-blennies ( tailspot, their awesome, I have one )
-atlantic pygmy/ cherub angel
-yellowhead jawfish
-dottyback ( royal )
Here's a link to an awesome guide to nano fish:
http://www.nano-reef.com/forums/inde...howtopic=74703
Good luck
