The staff at your library will be able to tell you if they stock the books, just tell them the name of the author and they'll be able to look it up for you. If the book you want is out on loan they can reserve it for you.
If your local library doesn't have them then other libraries in the area might have them, in which case your local library can obtain the book for you for a small fee.
If you're open to buying used books you can often find them online. If I want paperbacks (I read them in the bath!) I use a company called Abe Books which was recommended by another Rootschatter. For instance, the first of Nathan Dylan Goodwin’s series, Finding the Past, is currently available for 80p, plus £2.20 postage. There are several more, a number of which are only slightly higher prices.
I hope you manage to read them, one way or another.
