Ok, I'll narrow my critisism to what was offered -- 50 Sudoku's of unknown (and unknowable without purchase) quality in PDF format -- that must be downloaded by your mum -- and printed -- they cannot be solved on screen -- for a pound.
Why? As I said, there are multiple sources that match and exceed these criteria at NO COST.
Comparing head to head -- Sudoku's suitable for printing without installation, registration, signup, payment or even "download" beyond simply clicking to open a webpage:
(this is NOT a complete listing -- there are many more)OpenSky Sudoku Generator will generate PDFs
on the fly containing 1 to 50 Sudokus, either 1 or 4 per page, with or without solutions included in 4 difficulty levels. *Free*. That's over a grazillion puzzles on this one site. If you want more ...
Printsudoku currently has over 600 free Sudokus in PDF format in 5 levels plus a variant. *Free*.
Krazydad currently has some 4000 Sudokus in PDF format in 5 difficutly levels. *Free*.
Some newspapers have their puzzles online:
www.
timesonline.co.uk/section/0,,18209,00.html { broken link } -- The Times puts its Sudokus (by Pappocom) online -- they have several difficulty levels and also include some variants and a recent archive. They are not in PDF format but can still be printed. *Free*
www.
sudoku.org.uk/backpuzzles.htm { broken link } -- The Daily Telegraph[/url] has a archive of puzzles from the paper in PDF format. *Free*.
The Guardian seems to have every puzzle they've ever published available in PDF format. *Free*.
The Daily Mail has a large archive online in a print-friendly (though not PDF) format. *Free*
Vegard Hanssen's website has some 7 million puzzles -- Standard Sudoku's in 8 levels plus the largest selection of variants available anywhere, on or off the web, several versions which are original. No PDFs but a clean print facility. *Free*
Paul's Pages has a 750 puzzle gallery in 5 levels -- plus it will generate random puzzles. They're not PDFs, but there is a nice, clean print option -- in fact, it can be used to print Sudoku's from any source.
Astraware's Sudoku of the Day has 6 puzzles a day in 6 levels and a two week archive -- plus step by tedious step solutions. *Free*
Sudoku Susser does not generate puzzles, but will fetch several million of them from the web for you and print them. *Free*, runs on mulitple platforms and has no draconion installation -- just a zip file to be unzipped (windows version). *Free*
Of course,
Simple Sudoku is free and requires only a minimal, non-invasive intallation. Five levels, easy to print. *Free*
Although
Solo is software that should be downloaded -- the Windows version (it's available for Mac, Unix and Palm OS as well) requires no installation. Just click on the file, save it and run it. Actually, you don't even have to save it -- you can run it online. It generates an unlimited number of puzzles in 6 difficutly levels, 8 symmetry choices, mutliple sizes with easy printing. *Free* and open source.
Dell's new monthly Sudoku magainze (Dell -- the publishers who introduced Number Place 30 years ago), has over 175 puzzles for $3 -- subscribing lowers the price further. You get an actual printed magazine rather than wasting your toner and paper. Plus, they included Sudokus that include the diagonal and other variations. ($3 US is about one and three quarters pounds.)
This is by no means a complete or definitive list. Is there *one* of these options that isn't far superior to what the original poster is offering?