Further to yesterday's post about speakers:
(Image source: Flickr user Enrico Salad)
If you're looking for some reading matter to ease you into loudspeaker design and construction, do not buy Vance Dickason's famous, though now out of print, Loudspeaker Design Cookbook. Even getting a pirated PDF of it is not a great idea. This is because the Design Cookbook is for people who already know what they're doing - its subtitle is "Everything you Need to Become a Better Speaker Designer", emphasis mine. You're going to have to learn about Thiele/Small parameters and some other technical stuff at some point if you're building most kinds of multi-driver and ported loudspeaker, but there are several kinds of speaker you can build without doing anything beyond basic arithmetic.
There are a ton of books about speaker design, most of which I've never read, so maybe I'm about to suggest you go in a non-optimal direction. But the best book I have read on the subject is V.A. Capel's An Introduction to Loudspeakers and Enclosure Design, which is also out of print but can still be had cheaply on Amazon and on eBay (there are local Australian and UK sellers!UK sellers!).
An Introduction to Loudspeakers and Enclosure Design does what it says on the tin, and includes detailed instructions for building one of those single-cheap-driver transmission-line speakers I'm so keen on. If you build it according to the instructions you'll end up with a folded transmission line with ceramic-tile reflectors on the corners; I'm pretty sure just making the reflectors out of wood wouldn't significantly hurt performance.
(Image source: Flickr user Moisturizing Tranquilizers)
You don't have to do all the extra woodwork required to make a transmission-line enclosure, though. A simple sealed box with one driver will do.
There's a whole subsection of the audiophile world - both the empirical and the woo-woo side - devoted to single-driver speakers, and such a speaker is a really good option for your first speaker project.
(Image source: Flickr user drosen7900)
A solidly constructed box with a single cheap driver can sound remarkably good, especially if the speakers are close to the listener, even though the response plot reports high treble and low bass are missing, presumed dead, and the midrange response looks like a Worms battlefield.
...but now that few people use CRT monitors and TVs, you can build your own computer or hi-fi/home-theatre speakers without even bothering to use magnetically shielded drivers. Any dirt-cheap paper-cone wideranges, or multi-driver round or oval car speakers (which are not strictly speaking single drivers, but can sound good just the same) will do.
And for your first project, all you need is a sealed box, the bigger the better, with one hole in the front that roughly fits a single driver. You will probably need to be able to solder, but not a lot of work is involved, and what work you do have to do can be quite sloppy and still give a perfectly functional result. (Think of it as the Roman Army knife of loudspeakers!)
Oh, and on the subject of very heavy speaker cabinets: What do you do if you've already got some speakers, but you want their cabinets to be less resonant?
(Image source: Flickr user Voxphoto)
Just cast your own speaker stands out of concrete, and bolt the speakers onto them!