The reason for drying wood is to produce a stable wood, with reduced cracking, and increased strength. The problem with drying wood is that it "moves", that is it warps, twists, bends and generally wants to contort in anything but a straight piece of wood, and each species has it's own unique characteristics.
Drying wood slowly under controlled conditions can be cost effective and provide a quality wood source. There are a couple of types of wood drying alternatives namely Solar and Air-Evaporation.
Solar, as the name suggests relies on the sun to dry the wood slowly over a few weeks or months depending on weather conditions. Similar to how a greenhouse works, and is very effective is it's operation in that during the day the wood heats up, gives off a bit of water, then at night it "relaxes" and cools off. In this way it only gives off a small bit of water at a time thereby helping to keep the wood more stable while still drying it very effectively.
Evaporation type drying rooms use small household dehydrators to draw moisture from the air and thus dry the wood through a process of osmosis. These also work very well but in all cases the wood needs to be monitored closely as drawing too much water off too quickly can make the wood check (it might check anyway regarless of what you do) or it might warp badly or develope "honeycombing", something that wants to be avoided at ALL costs.
Both of these processes can be used to construct small, safe and very cost effective drying rooms, particularly if a few people are involved. The advantage of building your own drying room is that not only do you have full control over the wood you are drying, you also have the flexibility purchasing "green wood", which is normally at a much reduced price.
If you are interested in controlling your wood source and possibly saving money, check out wood drying for yourself and here are some very good sources ....