High and welcome Nugget123.
First let me say you are going about this the right way. I read so many posts that start out something like "I threw some seeds in a glass of water 2 days ago and they have little white tails....what do i do now."
The most important piece of growing equipment is knowledge.
People could answer your Q's 1 by 1, but a much much better way to aquiring knowledge before you drop seeds is reading a grow book. In fact, 2 or 3 of them. People who do some reading increase their chances of success 1000%.
There are many grow books available, many of them free, on-line.
I'm partial to books; something you can hold in your hand and is way more convienent than a computer. You can buy grow books at any major book store. Anything by Ed Rosenthal is good.
So maybe buy one and read one on-line.
Here's a nice on-line grow guide.
http://my.marijuana.com/Bible.php?loc=2&id=1
Re: your 1st Q:
Doing an internet search on seed banks will give you a list of companies that sell seeds. However, for 1st-time growers I recommend seeds you find in the pot you buy. You want to look for fat brown seeds.
They are free, and in the case of Mexican schwag, very hearty. An excellent choice for a first grow since they can take a lot of abuse and still yield you bud. The bud won't be ultra-killer, but it will give you an idea of the basics.
And you will end up with pot lots better than the pot the seeds came from, since most commercial pot is mistreated, esp. in harvesting, transportation and storage.
And it will be better simply because YOU grew it.
My advice:
Read a few grow guide's. If you deciede to grow indoors, construct a grow space first.
Don't worry about hydro or DWC or scrog (you'll learn what these are by reading). To me, the best way to start is in quality potting soil, under HPS light (ideally 50 watts per sq/ft.)
During you first grow, if you encounter a problem not covered by a grow book, feel free to ask here.
Also, cruise sites like this and read other grower's posts.
Simply put, the more you know the more you'll grow.
Growing your own is fun. Even better is getting great pot for pennies rather than dollars. For a simple basic closet grow, you may spend $300.00 and a few hours to get started. Then maybe $100 in elect & nutrients over the next 4 months.
And you'll make that all back with the first harvest.
Example: grow 8 plants under a 400-watt HPS that yield an oz. per plant--bam that's a half a pound right there. I don't know how much a half a pound of mid-grade buds cost in your neck of the woods but I bet it's more than the $400.00 it costs you to grow your own.
So read read read.
And keep us posted on your progress, because we care, and want you to succeed.