fyreflye
Circles of Power, was a favourite of mine. A good practical guide that filled in a lot of the gaps back then. It's a shame it will probably never be reprinted. One of Greers latest books seems to be a sort of rehash, but he's gone and given it a top to bottom 'Celtic' make over and re-branded it, Druid Golden Dawn, or something like that. Not my cup of tea really.
Though OP, reasonably priced used copies of Circles of Power without its druidic makeover are still available from marketplace sellers on US Amazon. Don't know about its availability in the rest of the world.