Starting Up A 20 Gallon Live Tank

[phantomlink]

I'm starting up a 20 gallon long corydora tank soon and had a few questions.  I want to plant it with crypts and any small grass I might find.  I'm going to use playsand for the substrate and will buy a shoplight for a cheap diy lighting system.  Heres what I'm wondering:
 
Some of the shoplights are t5, will these work like the crazy expensive t5s at the fish store?
 
the store has a really small selection of plants and expensive, I've found some online for $2 or less with free shipping.  How long can plants stay alive during shipment as compared to fish?
 
I saw some fert tabs at the store that says you place them in the sand every 6 inches or so and replace every 2-3 months.  Will these work well for crypts?
 
I dont plan to inject co2, I dont feel I'm ready for that kind of aquarium setup yet, and I just finished paying off my tanks I started in the summer I dont want to get into debt again going high tech.  Will too much ferts and not enough co2 kill the plants or kill the fish?  My main goal here is to keep the cory and kuhli alive

 

[phantomlink]

I have a regular T8 light from my 20 gallon tall, if I use that for a light and just get a cheap piece of glass cut for a lid to keep things cheap, since its 6 inches shorter will the light technically be more powerful since theres less distance to travel?  I know a 20 gallon long is longer then a normal 20, so the light wont cover the entire tank but if I center it then I could put some crypts in the center where the light is concentrated