It probably depends on location, but around here, giving stuff away is easy. There are several for profit thrift stores in the area, some of which will let you

It probably depends on location, but around here, giving stuff away is easy. There are several for profit thrift stores in the area, some of which will let you just drop stuff off for them. There are also several non-profits that will accept donations and write you a receipt you can use for tax purposes. I've also seen collection receptacles in various parking lots (as well as the county dump). I've been able to get the local branch of Habitat for Humanity to come to me with a truck to pick up some old furniture free of charge. The only downside was that they are not allowed to come into houses, so I was responsible for moving the furniture to the yard. For buying stuff, the local thrift stores are good, and offer very low prices on everything. The only downside is you actually need to show up, and are limited to the items they have, so it is not an option if you have a specific thing in mind.