where to get Soil/seeds

is there anywhere i can pick up some cheap/good quality seeds/soil .... like a local shop for soil.. i was looking into foxfarm or sunshine mix 4 but would they have either of these at like a homedepot/kmart/walmart something ? or a cheap online site and is there anywhere i can get some good seed's under like 100 bucks (usd) most of the place's are like 70 pounds for some decent seeds... im thinking of goin with misty from nirvana around 35 usd ... but if i could find some cheaper c99 or something else fun i would look into that

also does anyone know a good carbon filter/odor nutralizer for a small place like.. 2x4x3 for a few plants..... im gonna pick up one of those odor removing bulbs.... but will that cut it ? or am i gonna have to put a big carbon filter in there

and the verdict is