I read a lot of books. More of this anon (I know I keep promising this).
People often say things like 'the NAs are difficult to find'. It's certainly expensive and time-consuming to locate, buy and read all of them. Remember that the NA/MA/EDA/PDAs were released one or two at a time for the best part of fifteen years, so trying to collect the whole range in one go will be like trying to swallow an elephant.
There are books available for free online, including my novel The Dying Days (the first original novel featuring the eighth Doctor) at: www.bbc.co.uk/doctorwho/classic/ebooks/.
And you can still find bargains at Amazon Marketplace and Ebay.
A site I use a lot to feed my insatiable book habit is:
And a quick check shows that there are a lot of old Doctor Who books on there.
I've also started using www.greenmetropolis.com and they've got
a smaller range (and are UK-only), but the books are cheaper and you save the planet and stuff, and surely that's what the Doctor's all about.