This Society produces a useful booklet "Machynlleth Town Trail" written by David Wyn Davies - other works by the same author are available locally. Also relevant are "Railway through Talerddig" (G Briwnant-Jones) and "Slate Quarrying at Corris" (A J Richards).
Web sites -
Civic Trust for Wales (umbrella body for civic socs)
CADW (historic Welsh buildings authority)
National Library of Wales (at Aberystwyth)
Clwyd-Powys Archaeological Trust
Countryside Council for Wales
Ynys Hir - RSPB wood and wetland reserve.
Glaslyn - moorland nature reserve.
Glyndwr's Way walking trail
National Cycle Route network (Sustrans)
Local on / off road bike trails
Mainline Rail travel (interactive - times & fares)
Tourist information for Wales
A compendium of local interest (by Dick Williams)