I recommended above that looking for good teach-yourself finance textbooks in places where they sell secondhand books would be useful.
As an example, look at this superb textbook I found last week - at NZ$7.00 it was a steal. It provides a self-contained course in the fundamentals of corporate finance, which forms "the other side" of personal investment: Re: What books are you reading? - Fundamentals of corporate finance.
The CD-ROM of mostly Excel spreadsheets is very handy and a smart way to teach/learn.
I bought the book to help coach my 15 y/o daughter.
There will be more - the same or similar - such books in any place that sells secondhand books.
As my old accountancy lecturer used to say: "Never pay retail and always ask for a discount - especially for paying in cash - or buy good second-hand stuff."
Picking up old textbooks for a song is a no-brainer to keep study costs down. Textbooks are regularly updated to make money and each new edition is sold at a huge mark-up, whilst previous editions go for a song, even though the basic content of accounting/finance textbooks usually varies little and doesn't age between editions.