Try this source - UK based but they do stock it.
Plain Matrix Board, Eurocard and Copper Stripboard, used for manufacturing and proto typing electronic circuits
www.esr.co.uk
or here:
This matrix board has been manufactured in SRBP (0.1in) grid. Hole diameter 1mm Hole Pitch: 2.54mm Length: 160mm (60 holes) Width: 100mm (38 holes) Total 2280 holes
www.bowood-electronics.co.uk
or eBay:
Great for prototypes and one off designs. Board Thickness:1.5 mm. Material:Hard Paper. Spiratronics Part Number. Width:100 mm.
www.ebay.co.uk
Notwithstanding the above, I have been using this stuff for a few years now:
The solid copper-coated side makes a great earth plane and can make prototype construction very compact (all your ground connections solder on the component side and you use a small drill bit to give clearance to component wires that need to pass through to be wired point-to-point).
It might look complicated but it's surprisingly simple to use and the compactness of the finished results is quite astonishing - I'll try to upload a pic or two of some stuff I've done over the years but, as ever, each to their own!