The Popular Mechanics "Shop Notes" books have been read now, cover to cover at least twice, and I fear the number of bookmarks in the books make them lean when stacked.
I saved up and bought the reprint set through Lee Valley tools a few years ago, and have used some of the methods and ideas in there at work from time to time - a wonderful reference.
The link to the set is here, and currently costs $165 USD. You can buy the books in sets of 5, or as individual books, so budgeting can be eased. I cannot recall the exact shipping charges to Oz, but I know it was quite reasonable considering the number of books.
Each book is roughly the same size at 240mm x 165mm x 15mm (H x W x T) although the thickness does vary a little with some books being 12mm thick, and others at 18mm thick. The books are all black and white reprints, and of excellent quality and reproduction.
The picture below is from the Lee Valley page noted above.
If you can afford it, there are two other sets of books well worth looking at from Lee Valley (not saying the rest aren't good, but these are ones I can reccomend based on reading them...)
The first other suggestion is the "Boy Mechanics" series - it's a set of four books, each the size of a novel. They remind me of the books my Dad had when he was young, all about things boys can build from timber, salvaged materials, etc.
UPDATE!!! - Whilst checking for the link I found this set is being discontinued and is heavily marked down!!!! A shame, but don't miss out. The link to the series is here through Lee Valley
The picture is again from the Lee Valley webpage. Some of this series can be bought for a similar (discounted) price from Amazon like this.
The last set of books I grabbed from Lee Valley was the "Bull of the Woods" books. They are a series of machinist orientated cartoons. There is a similar cartoon in the old Model Engineer magazines about "Chuck, the Muddle Engineer", but the "Bull" series is more serious, but just as funny. The books are the size of a Reader's digest, and each cartoon is a single frame, one per page. Here is the link from Lee Valley, and the picture below.
These books represent a valuable archive of knowledge and ideas from the period of time when machines were powered from shafts and belts, and CNC and computers were unheard of, HSS was a new thing, and even electric motors were a rarity.
The Popular Mechanics set includes gems such as how to turn a pulley of 28" diameter on a lathe capable of only 16", or how to lift several tonnes of line shafting up into the shaft hangers without using a crane - the list goes on and on... If I had to choose only one set from the three mentioned here, this would be the set. I hope my own children will learn from the sets as much as I have.
NOTE: Just a general note about the postings discussing books. Where possible I'll provide links to purchasing the books, and try and provide options. Typically Amazon will carry the books at the best price, but there is the odd, rare occasion where it's cheaper elsewhere, or amazon doesn't carry the books. In those cases I'll provide links, and comments to that effect - it's nothing against Amazon (goodness knows they get enough of my money as it is), but I try to stretch my money as far as possible, and presume others have the same limitations...