New to indoor, just a few questions..

Just have a few questions, I've got 2 4 foot fluorescent fixtures with 4 40w gro-lux bulbs, I'm also planning on getting 2 Cfl's for the sides when the plants start getting taller, but I just wanted to know, under this light, how many plants can I grow?

Also, I live in Toronto, anybody know where I could get some reliable seeds at a decent price without any heat?

Any info would be appreciated

Thanks,