Lol i was about to post something like this.
Back to topic, Petcetera carries a number of good small tanks, and i do believe walmart as well.
Petlands i have heard they have fairly good stock, etc (none here in etown)
If you wanted to go standard size, you could perhaps get the hood/tank kit from walmart, and put in 2 13-15 watt screw in bulbs (for low-med light perhaps)
and for filtration? well a number of choices exist, but i would go with an Aquaclear 20, as dwarf puffers aren't all that clean.
Any types of plants in particular?