@jhonathenblazer
Hey bro, glad to hear you're thinking about starting your grow.. I think most of us here learned or are learning how to grow plants from watching threads on forums or DVD's and books.
So it's really cool you'd like to start and for a tent of those measurements I think you should go with a 600W lamp..
And it all depends on what kind of grow you'd want to attempt.. if you want many small plants I think you could fit 15 pots in there definitely.. But the yields per plant aren't going to be staggering or anything.. I'm thinking of doing 7 or 8 medium sized plants hoping to yield about 60 grams each (about 2oz.)
But you could also go with 4 large plants and make an attempt at getting maybe 5 oz. a plant it's all possible..
And like firekilla said, picking a strain is something you should feel comfortable doing cause this is what you're going to be smoking soon..
For ease of growing and a wonderful weed, I'd recommend Northern Light.. for pain in the ass growing and top quality ganja.. go White Rhino

So it's all about what you want in the end ofcourse.. so get your equipment up and start a journal
And green I feel your pain bro.. but I know the sad reality man.. Some places I know they ask the most ridiculous prices for weed full of seeds...
And worst of all is that it doesn't even make you high...
Update*
Anyways got an update coming tomorrow.. major one, plants aren't doing too well..
I was a bit upset today and didn't take pictures, but the burning has gotten worst and it's all because of some major temp. fluctuations in the room where they're growing..
The temp. in the room swings from 82 to 98, and it's affected one of the White Rhino's and the El Niño drastically.. the plants are completely stunned and have not grown for the past week I'm affraid.. or atleast I haven't seen any further growth.
I added a small intake fan in there but I think it needs a much bigger exhaust fan..
What's happening is that the room temp. is so high that it sucks moisture out of the leaves and what's left is nutrients to cause a burn.
So even though the leaf tips don't seem burned, and one can say it's nutrient deficiency, it's actually an awful ugly burn..
If anyone got some tips or ideas on whats up, please comment..
I'll have some pics up tomorrow so you guy can see.. It's really fucked up cause the plants were doing so nice..
Btw.
I lowered the nutrient intake by about 20% to start the end flowering.. And also raised the lamp higher..
PH at 6.5
EC at 2.0