Roger Millington Publishing...
Where to find Packie's books and recordings
Recollections is out of print. But you can get an eBook version from the Kobo bookstore!. Other outlets, including (hopefully) a way to order a printed copy, to follow. Flanagan is currently not being distributed. An eBook version is in the works. If you are looking for printed copies, for now the best bet is to look for used copies on Amazon.
Your local music store should be able to get you a copy easily enough. In North America, you can order directly from the publisher, Mel Bay. On-line, you can get it from The Whistle Shop. In the UK, you'll probably have to go to a music shop.
You can order this directly from the publisher in the UK, Veteran.
You may be able to find LPs second-hand on the web. Try Little Pot Stove records in the UK.