Goblin Deck-help please!

While having those big bombs is fairly traditional, you'll find a lot of goblin decks don't go beyond three mana and run +/-18 land.

The only exception (beyond three mana) I like is Krenko, Mob Boss.  I used to play with him all the time. Now he is in my sideboard.

Think about synergies you can get with other cards, and you can come up with some really nasty plays. Cards like Dynacharge take three 1/1 goblins that are swinging for three up to nine when overloaded (each of your attacking creatures gets +2/+0 until the end of the turn).  Kicking Goblin Bushwhacker (R+R) is another way to add a little extra hurt.

I like this tempo:

T1: Legion Loyalist, swing for one.
T2: Krenko's Command (or Dragon Fodder if playing modern); swing for one (the Loyalist).
T3: Play Goblin Bushwhacker kicked (your creatures get +1/+0 until end of turn and have haste), play the land named Teetering Peaks (target creature gets +2/+0 until end of turn); swing for 10 with First Strike, trample, and you cannot be blockec by creature tokens (Legion Loyalist's Battalion ability).

Your alternate T3 uses Dynacharge overloaded as I described earlier.  If you pull off the T3 I listed above and all damage resolves, then Dynacharge on T4, it's over unless they have blockers and/or removal (swing for 12).

Of course, cards like Goblin Chieftain and Goblin King are great, too.  Bloodmark Mentor gives all red creatures you control first strike. Goblin Wardriver (RR) is another fun one that gives all other attacking creatures you control +1/+0 until end of turn.

If you decide you really like goblins after playing them a while, you can start chasing cards like Warren Instigator, Cavern of Souls, Aether Vial, and Quest for the Goblin Lord. Valakut, the Molten Pinnacle can be really fun, too.

In addition to fun goblins, be sure to include some extra burn spells for removal, like Lightning Bolt. Goblin Arsonist also is a nice T1 option. Goblin Balloon Brigade is  great sideboard option against fliers.